TNT2015 Abstracts and Posters Book by Phantoms Foundation

Abstracts & Posters book

Graphene & 2D Materials International Conference and Exhibition

TNT2015 index

Foreword

Committees

Poster awards

Sponsors

Exhibitors

Speakers

Abstracts

Posters

140

On behalf of the International, Local and Technical Committees, we take great pleasure in welcoming you to Toulouse (France) for the 16th “Trends in NanoTechnology” International Conference (TNT2015).

TNT2015

Foreword

TNT2015 is being held in large part due to the overwhelming success of earlier TNT Nanotechnology Conferences. This high-level scientific meeting series aims to present a broad range of current research in Nanoscience and Nanotechnology worldwide, as well as initiatives such as MANA/NIMS, CIC nanoGUNE, IBEC, DIPC, ICN2, etc. TNT events have demonstrated that they are particularly effective in transmitting information and promoting interaction and new contacts among workers in this field. Furthermore, this event offers visitors, exhibitors and sponsors an ideal opportunity to interact with each other. This year, a Graphene one-day Symposium will again be organized within TNT2015 in collaboration with ICN2 (Spain). This Graphene Day will entail a plenary session during the morning and the afternoon session will be divided in 2 tracks: Graphene science driven contributions including Graphene in "Grand SudOuest" region (France) and Graphene driven applications Keynotes. One of the main objectives of the Trends in Nanotechnology Conference is to provide a platform where young researchers can present their latest work and also interact with high-level scientists. For this purpose, the Organising

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Committee provides every year travel grants for students. In addition, this year, awards will be given to young PhD students for their contributions presented at TNT. More than 40 senior scientists are involved in the selection process. Grants and awards are funded by the TNT Organisation in collaboration with private bodies and several governmental/research institutions. TNT is now one of the premier European conferences devoted to nanoscale science and technology. We are indebted to the following Scientific Institutions, Companies and Government Agencies for their financial support: Phantoms Foundation, Universidad Autónoma de Madrid (UAM), ICEX España Exportación e Inversiones – Invest in Spain, NIMS (Nanomaterials Laboratory) and MANA (International Center for Materials and Nanoarchitectonics), Institute for Bioengineering of Catalonia (IBEC), European Physical Society (EPS), SO Toulouse, SICOVAL, DIAGORA, IfiMAC – Condensed Matter Physics Center, Scienta Omicron, AIRBUS, CNano GSO, NEXT and INL (International Iberian Nanotechnology Laboratory). We would also like to thank the following companies and institutions for their participation: Raith Nanofabrication, Scientec - Prevac, Scienta Omicron, SENSIA, SPECS Surface Nano Analysis, Fundación Argentina de Nanotecnología and ICEX España Exportación e Inversiones – Invest in Spain. In addition, thanks must be given to the staff of all the organising institutions whose hard work has helped planning this conference.

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Organising Committee

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TNT2015 Committees Organising Committee

Technical Committee

Jose-Maria Alameda (Universidad de Oviedo, Spain) Masakazu Aono (MANA / NIMS, Japan) Robert Baptist (CEA / DRT / LETI, France) Xavier Cartoixa (UAB, Spain) Antonio Correia (Phantoms Foundation, Spain) – Conference Chairman Gianaurelio Cuniberti (TUD, Germany) Pedro Echenique (DICP / UPV, Spain) Jose Maria Gonzalez Calbet (UCM, Spain) Uzi Landman (Georgia Tech, USA) Jose Manuel Perlado Martin (IFN-ETSII / UPM, Spain) Jose Maria Pitarke (CIC nanoGUNE, Spain) Ron Reifenberger (Purdue University, USA) Jose Rivas (Santiago de Compostela Univ., Spain) Stephan Roche (ICN2, Spain) Juan Jose Saenz (UAM, Spain) Josep Samitier (IBEC - Universitat de Barcelona, Spain) Frank Scheffold (University of Fribourg, Switzerland) Didier Tonneau (CNRS-CINaM, France)

Carmen Chacón Tomé (Phantoms Foundation, Spain) Viviana Estêvão (Phantoms Foundation, Spain) Maite Fernández Jiménez (Phantoms Foundation, Spain) Paloma Garcia Escorial (Phantoms Foundation, Spain) Pedro Garcia Mochales (UAM, Spain) Adriana Gil (CSIC, Spain) Conchi Narros Hernández (Phantoms Foundation, Spain) Joaquin Ramon-Laca (Phantoms Foundation, Spain) Jose-Luis Roldan (Phantoms Foundation, Spain)

Local Organising Committee Xavier Bouju (CEMES/CNRS, France)

International Scientific Committee Masakazu Aono (MANA / NIMS, Japan) Emilio Artacho (CIC nanoGUNE, Spain) Andreas Berger (CIC nanoGUNE, Spain) Fernando Briones (IMM / CSIC, Spain) Remi Carminati (Institut Langevin, ESPCI, France) Jose-Luis Costa Kramer (IMM / CSIC, Spain) Antonio Garcia Martin (IMM / CSIC, Spain) Raquel Gonzalez Arrabal (IFN-ETSII / UPM, Spain) Pierre Legagneux (Thales, France) Annick Loiseau (ONERA - CNRS, France) Josep Samitier (IBEC - Universitat de Barcelona, Spain)

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TNT2015 Poster awards

Funded by

Award

European Physical Society

200 Euros

Phantoms Foundation

iPad Mini 16GB - WiFi

TNT 2015 Organisation

Free registration to the 2016 2016 Conference

“PASSPORT TO PRIZES” PROGRAM At this new edition of the Trends in Nanotechnology conference we are pleased to organise the TNT2015 “Passport to Prizes” program. How does the “Passport to Prizes” program work? Each TNT2015 attendee will be issued a passport card at registration. This card contains the logos of all exhibiting companies. You will take your card around the exhibit hall on Monday, Tuesday and Wednesday and collecting stamps from the participating exhibitor companies listed on their passport. For that exhibitors will be given a stamp with a number. Once you have completed your passport card with 7 stamps, fill in your personal data and take the card to the ticket tumbler located in the Registration Area. Please, do not forget to complete the passport card with your name and institution before you put it into the box. All completed entries will be eligible for a prize drawing that will be conducted on the evening of Wednesday (09/09/2015) during the Poster Award Ceremony. Do not miss this opportunity to win a Tablet LEOTEC L-Pad Meteor DCX (donated by Phantoms Foundation). And remember that winners need to be present to win. So… see you at the conference dinner and the poster award ceremony!

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TNT2015 Sponsors

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TNT2015 Exhibitors

Raith is a leading precision technology solution provider for nanofabrication, electron beam lithography, focused ion beam fabrication, nanoengineering and reverse engineering applications. Customers include universities and other organizations involved in various fields of nanotechnology research and materials science – as well as industrial and medium sized enterprises that use nanotechnology for specific product applications or produce compound semiconductors. Founded in 1980 and headquartered in Dortmund, Germany, Raith employs more than 200 people. The company works as close as possible with customers in the most important global markets through subsidiaries in the Netherlands, the USA and in Asia and through an extensive partner and service network. Raith GmbH Konrad-Adenauer-Allee 8 44263 Dortmund- Germany Phone: +49 (0)231 / 95004 - 0 Fax: +49 (0)231 / 95004 - 460 Web: www.raith.com

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ScienTec Ibérica, is the spanish branch of ScienTec France, its mission is to serve and attend the Iberian Nano-micro surface analysis market from its office in Madrid. Its field of activity is related to scientific research, R&D and industrial metrology. In terms of product line, we deal with atomic force microscopes, contact profilometry, digital holography, interferometry, nanoindentation, filmetrics and high aspect ratio confocals ScienTec Ibérica accompanies you in your various projects by offering system adapted to your applications (nanotechnology, polymer, material surfaces, biology, semiconductor, microfabricaiton and the cutting tool industry…) ScienTec Ibérica C/ Rufino Sánchez 83 28290 Las Rozas (Madrid) Phone: 91-8429467 Fax: 902-875572 info@scientec.es Web: www.scientec.es

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Scienta Omicron was formed on May 28 2015 by the merger of two of the most renowned companies in the field of Surface Science: VG Scienta and Omicron NanoTechnology. It now forms the leading innovator in Surface Science providing top capabilities for the research community in - Electron Spectroscopy, e.g. the full range of electron spectrometers ARPES Systems XPS systems High Pressure XPS systems LEED, PEEM - Scanning Probe Microscopy. e.g. Low Temperature SPM Variable Temperature SPM 4 Probe SPM and the full range of STM and AFM techniques - Thin Film & Tailored Systems, e.g. our MBE series PRO, EVO and Lab 10 customised solution including ALD, PLD, CVD, PVD, etc. These capabilities are available in custom tailored solutions from one source with worldwide sales and service groups. Web: www.scientaomicron.com

The Argentinian Nanotechnology Foundation (FAN) is a nonprofit private organization created by the Argentinian Ministry of Science, Technology and Innovation in 2005. Our network gathers more than 100 local nanotech companies and the main nanotech researchers of Argentina. We have worked in more than 60 nanotechproduct development projects of which one third are in cooperation with Europe (Nanopymes Programme). We offer strategic and trustable partnership in nanotech field.

Fundación Argentina de Nanotecnología

25 de Mayo 1021 Villa Lynch (1650) Partido de San Martín - Buenos Aires (Argentina) Phone: +54 (0)114518-1716 Mail: innovacion@fan.org.ar

SPECS Surface Nano Analysis GmbH - A Story of Constant Innovation SPECS has more than 150 employees at its headquarters in Berlin and its subsidiaries in the USA and Switzerland. The company also has sales offices and international sales channels in more than sixteen countries. A team of scientists and engineers are involved in developing and producing scientific instruments for surface analysis, material science and nanotechnology. By constant innovation new techniques, components or system concepts are launched every year since more than 30 years, revolutionizing the field of surface analysis. Contact SPECS Surface Nano Analysis GmbH (www.specs.com) for further information.

ICEX Spain Trade and Investment (INVEST IN SPAIN) is the Government organization that supports foreign companies seeking to set up or expand their business in Spain. The organization provides comprehensive, efficient and confidential consultation at no cost during all stages of investment process, from planning and evaluation, to start-up and post-investment services. The services include the provision of information, analysis and tailor-made reports on a wide range of topics including project costs, tax and incentives, administrative procedures, etc. The dedicated and professional guidance is guaranteed by assigning a project manager to the case who will become the longterm strategic partner. Web: www.icex.es

Web: www.fan.org.ar Web: www.sensia.es

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Index alphabetical order

TNT2015 Speakers

page Guillermo Acuna (TU Braunschweig, Germany) “DNA Origami for plasmonics and fluorescence applications” Pedro Alpuim (INL - International Iberian Nanotechnology Laboratory, Portugal) “Electrolyte-gated graphene field-effect transistors for biosensing applications fabricated at the wafer scale” Albert C. Aragonès (University of Barcelona, Spain) “New applications, effects and fundamentals in single-molecule wires” Jordi Arbiol (ICREA & ICN2, Spain) “Photonic 1D nanomaterials: Correlation between Optical Properties at subnanometer scale with its structure at atomic scale” Antonio Avila (Universidade Federal de Minas Gerais, Brazil) “Non-covalent Functionalization of Carbon Based Nanostructures and Its Application to Carbon/Epoxy Composites” Adrian Bachtold (ICFO, Spain) “What is the difference between a graphene mechanical resonator and a music drum?” Ioan Bâldea (Universität Heidelberg, Germany) “Important impact of the experimental platform on the efficient simultaneous control of electronic and vibrational properties of molecular junctions” Edwin A. Baquero (LPCNO INSA-Toulouse, France) “Synthesis of InP/ZnS Nanocrystals Under Mild Conditions”

Laurent Baraton (GDF Suez, France) “Graphene and 2D materials in the perspective of a global energy player” Joanne Bartolome (Universitat Rovira i Virgili, Spain) “Preparation and characterization of carbon nanoonions modified electrodes for biosensor applications” Ofra Benny (The Hebrew University, Israel) “Targeting the Tumor Microenvironment with Polymeric Nanomicelles”

Keynote Plenary Session

Oral Senior Symposium Graphene & 2D Materials - Track B

Oral PhD Parallel Session

22 24

Keynote Plenary Session

Oral Senior Plenary Session

Keynote Symposium Graphene & 2D Materials

Oral Senior Plenary Session

Oral Senior Parallel Session

29 30

Keynote Symposium Graphene & 2D Materials

Oral PhD Parallel session

Keynote Plenary Session

Jean-François Berret (Université Paris-Diderot/CNRS, France) “Magnetic field-induced supracolloidal assemblies for micro-rheology applications”

Oral Senior

Thomas Blon (LPCNO - INSA Toulouse, France) “Ultra-dense array of single-crystalline cobalt nanowires” Peter Bøggild (DTU Nanotech, Denmark) “Non-destructive, large-area electrical characterization of graphene: a new light on defects” Roméo Bonnet (Université Paris Diderot, France) “Charge transport through functionalized multiwall carbon nanotubes”

Oral Senior

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Plenary Session

Parallel Session

33 34 35 36

Keynote Symposium Graphene & 2D Materials

Oral PhD Parallel session

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37 39

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Speakers

TNT2015

page Gaëtan Calbris (ICFO, Spain) “Investigating vector local field on optical nanostructure by phase-locked polarization-resolved near-field coherent imaging” Jen-Kun Chen (National Health Research Institutes/Institute of Biomedical Engineering & Nanomedicine, Taiwan) “Gold Nanoparticles Work as the Beta-emitter to Treat Brain Tumor” Miklós Csontos (Budapest University of Technology and Economics, Hungary) “A fast operation of nanometer–scale metallic memristors: highly transparent conductance channels in Ag2S devices” Lucy Cusinato (LPCNO, France) “Theoretical investigation for Fischer-Tropsch reaction with metal nanoparticles: building a relevant structural model, a mandatory prerequisite” Luisa De Cola (ISIS/Université de Strasbourg, France) “Dynamic and hybrid materials. Properties and applications” Marie-Anne De Smet (AIRBUS, France) “Research and challenges of optoelectronics systems in aeronautics” Fabien Delpech (Laboratoire de Physique et Chimie des Nano-Objets, France) “Unravelling the surface ligand of quantum dots: upgrading the NMR toolbox to see the invisible” Heinrich Diesinger (Institut d´Electronique, Microélectronique et de Nanotechnologie, CNRS UMR 8520, France) “AFM current-force spectroscopy of colloidal nanoparticle arrays” Glenna Drisko (Laboratoire de Chimie de Coordination, France) “Air-stable monocrystalline nickel nanorods and Ni-CNT hybrids for aeronautical applications” Pierre Fau (LCC-CNRS, France) “Self-Assembled Hollow SnO2 Octahedra for sub-ppm Gas Detection Sensors” Jochen Feldmann (LMU Munchen, Germany) “Optical and thermophoretic forces on plasmonic particles”

Oral Senior Parallel Session

Oral Senior Plenary Session

Oral PhD Parallel session

Keynote Plenary Session

43 44 -

Oral Senior Plenary Session

Oral Senior Parallel Session

Oral Senior Plenary Session

Keynote Plenary Session

Symposium Graphene & 2D Materials

Paulo Ferreira (The University of Texas at Austin, USA) “Understanding the Atomic Structure of Li-based Cathode Materials for Lithium-Ion Batteries by Advanced Transmission Electron Microscopy” Roberto Fiammengo (Istituto Italiano di Tecnologia (IIT) / Center for Biomolecular Nanotechnologies@UniLe, Italy) “Towards a Gold Nanoparticle-based Vaccine Directed against the Tumor Associated Mucin-1 Glycoprotein” Arianna Filoramo (CEA/IRAMIS/NIMBE/LICSEN, France) “High selectivity of pure semiconductor single walled carbon nanotubes for optoelectronic telecom applications” Emmanuel Flahaut (Universite Paul Sabatier CIRIMAT/LCMIE - CNRS, France) “Comparison of the environmental impact of carbon nanoparticles (carbon nanotubes, nanodiamonds, few-layer graphene)” Francisco J. Garcia-Vidal (UAM, Spain) “Strong coupling between organic molecules and surface plasmons”

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Plenary Session

47 48 49

Keynote

Xinliang Feng (Dresden University of Technology, Germany) “Graphene and 2D Hybrid Systems”

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Oral Senior

Keynote Plenary Session

Oral Senior Plenary Session

52 Oral Senior Parallel Session

Invited Symposium Graphene & 2D Materials

Keynote Plenary Session

54 55

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João Gaspar (INL - International Iberian Nanotechnology Laboratory, Portugal) “Hybrid Spintronic-MEMS Devices” Ehud Gazit (Tel Aviv University, Israel) “Bio-Inspired Building Blocks for Organic Nanotechnology” Arnaud Glaria (Laboratoire de Physique et Chimie des Nano-Objets (LPCNO), France) “Design of Copper-based Coatings for Bactericidal Applications” Luana Golanski (CEA/LITEN/DTNM/SEN/LNS, France) “Graphene monolayer produced on Pt reusable substrates for transparent conductive electrodes applications” César González (CEA Saclay, Service de Physique de l’Etat Condensé (DSM/IRAMIS/SPEC) , France) “Chemical Characterization of MoS2 using theoretical AFMcidation” Jean-Jacques Greffet (Institut d'Optique Graduate School, France) “Quantum optics with surface plasmons” Agnes Gubicza (Budapest University of Technology and Economics, Hungary) “Non-exponential resistive switching in Ag2S memristors: a key to nanometer-scale non-volatile memory devices” Konstantin Gusliyenko (EHU/UPV, Spain) “Effective Magnetization Damping in Inhomogeneous Spin Textures: Vortices and Skyrmions” Sabrina Habtoun (LAAS-CNRS, France) “AFM mechanical characterization and four-probe/SEM measurement of hybrid metallic/inorganic nanosprings” Kazutoshi Haraguchi (Nihon University, College of Industrial Technology, Japan) “Structures and Characteristics of noble metal nanoparticles in nanocomposites & gels via exfoliated clay mediated in-situ reduction” Cyrus Hirjibehedin (University College London, UK) “Tunable magnetoresistance in an asymmetrically coupled single-molecule junction” Hsin-Yun Hsu (National Chiao-Tung University, Taiwan) “Redox-triggered, self-disassembled silica-based nanoplatform for intracellular imaging and drug delivery”

Bilal Jabakhanji (American University of the Middle East (AUM), Kuwait) “Magnetoresistance in CVD-graphene on SiC” Felix Jimenez-Villacorta (ICMM - CSIC, Spain) “Graphene – silver nanoparticle interactions and their effect on Raman enhancement and transport properties” Christian Joachim (CEMES/CNRS, France) “Atomic scale Boolean Logic gates”

Plenary Session

Keynote Plenary Session

56 57

Oral Senior Plenary Session

Oral Senior Symposium Graphene & 2D Materials - Track B

Oral Senior Plenary Session

Keynote Plenary Session

60 62

Oral PhD Parallel session

Oral Senior Plenary Session

Oral PhD Parallel session

Oral Senior Plenary Session

Keynote Plenary Session

67 69

Oral Senior Plenary Session

Oral Senior Symposium Graphene & 2D Materials - Track A

Oral Senior Parallel session Graphene Track A

Keynote Plenary Session

72 73

Invited

Benoit Jouault (Université Montpellier 2, France) “The beauty of quantum transport in graphene grown on SiC”

Symposium Graphene & 2D Materials

Myrtil Kahn (LCC-CNRS, France) “Oxydation route determines the magnetic and relaxivity properties of iron oxide nanocrystals: toward highly efficient MRI contrast agent” Hsien-Chung Kao (National Taiwan Normal University, Taiwan) “Surface States in Weyl Semimetal Superconductors”

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Oral Senior

Oral Senior Plenary Session

Oral Senior Parallel Session

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75 76

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Speakers

TNT2015

page Ladislav Kavan (J. Heyrovsky Institute of Physical Chemistry, Czech Republic) “Optically Transparent FTO-Free Cathode for Dye-Sensitized Solar Cells” Marek Kolmer (Jagiellonian University, Poland) “Bottom-up formation of molecular wires on a semiconducting oxide: Aryl halides covalent coupling controlled by surface hydroxyl groups on rutile TiO2 surfaces” Andrey Kovalskii (National University of Science and Technology “MISIS”, Russia) “Hollow boron nitride spherical nanoparticles. Synthesis, structure and applications” Boris Kulnitskiy (TISNCM Tech. Ins. for Superharf and Novel Carbon Mat., Russia) “Diamond and lonsdaleite 13C and 12C formation in a diamond anvil high-pressure cell” Oleg Kurnosikov (Eindhoven University of Technology, The Netherlands) “Subsurface epitaxial growth of hidden Co nanoclusters” Dmitry Kvashnin (National University of Science and Technology “MISiS”, Russia) “Covalent heterostructure based on self-decorated MoS2 and graphene ” Lise-Marie Lacroix (LPCNO, France) “Ultrathin Au nanowires: towards 1D electronic properties” Philippe Lafarge (University Paris Diderot, MPQ, France) “Electron phonon interaction and quantum interference in molecular junctions”

Iban Larroulet (SENSIA, Spain) “Graphene and Nanotechnologies contributions to SPR in Sensia's experience” Guy Le Lay (Aix-Marseille Université CNRS, PIIM, France) “Progress in single layer silicene functionalization and in multilayer germanene growth“ Philippe Leclere (Université de Mons, Belgium) “Hybrid Organic/Inorganic Nanostructures for Energy Conversion and Storage Devices on Flexible Substrates“

Sébastien Linas (Université Claude Bernard Lyon1, France) “FIB etching of h-BN membranes for osmotic energy conversion” Luis M. Liz-Marzán (CIC biomaGUNE, Spain) “Templated Assembly of Nanoplasmonic Supercrystal Arrays”

David Mackenzie (University of Denmark, Denmark) “Comparative study of nano-scale and macro-scale field-effect mobility in CVD graphene” Markus Maier (Scienta Omicron, Germany) “Recent technology advancements in SPM based electrical probing at low temperatures” Xavier Marie (INSA-Toulouse, France) “Exciton Dynamics in 2D Semiconductors Based on Transition Metal Dichalcogenides”

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Oral Senior Plenary Session

Oral Senior Parallel Session

Oral Senior Plenary Session

Oral PhD Parallel Session

Oral Senior Plenary Session

79 81 82 83 84 85

Invited Symposium Graphene & 2D Materials

Oral Senior Plenary Session

Keynote Plenary Session

Oral Senior Symposium Graphene & 2D Materials - Track A

Keynote

Xing Ma (Max-Planck Institute for Intelligent Systems, Germany) “Surface Conductive Graphene-wrapped Micro-motors Exhibiting Enhanced Motion”

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Plenary Session

Annick Loiseau (ONERA, France) “Probing spectroscopic properties of BN and black phosphorous layers”

Manuel Marqués (Universidad Autónoma de Madrid, Spain) “The mechanical action of the spin curl optical forces”

Oral Senior

89 90

Keynote Symposium Graphene & 2D Materials - Track A

Oral Senior Plenary Session

91 92

Oral Senior Symposium Graphene & 2D Materials - Track A

Invited Plenary Session

Keynote Plenary Session

Oral Senior Plenary Session

95 96

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Jean-Daniel Marty (Université de Toulouse; UPS/CNRS; IMRCP, France) “Stimuli responsive hybrid nanomaterials: applications in drug delivery and imaging”

Artur Moreira Pinto (INEB / University of Porto, Portugal) “Effect of polymer surface adsorption on graphene nanoplatelets biocompatibility” Miguel Moreno Ugeda (University of California at Berkeley, USA) “Probing bandgap renormalization, excitonic effects, and interlayer coupling in 2D transition metal dichalcogenide semiconductors”

Kazuo Muramatsu (Incubation Alliance,Inc., Japan) “Development of Large Scale Production of Self-Standing Graphene” Sana Mzali (THALES RESEARCH & TECHNOLOGY, France) “Investigation of Metal Oxides Passivation for CVD Graphene 40GHz Photodetectors” Michel Nasilowski (Laboratoire de Physique et d'Etude des Matériaux, France) “Gold plated and thick shell quantum dots: two examples of colloidal quantum dots with much improved optical properties” Thierry Ondarçuhu (CEMES-CNRS, France) “Wetting properties of partially suspended graphene monolayers”

Amaya Ortega (AIMPLAS, Spain) “Graphene Based composites for conventional and additive manufacturing”

Plenary Session

Oral PhD Parallel session

Oral Senior Plenary Session

101

Keynote Symposium Graphene & 2D Materials

102

Oral PhD Parallel session

103

Oral PhD Parallel session

Invited Plenary Session

104 105

Oral Senior Symposium Graphene & 2D Materials - Track B

106

Keynote

Vittorio Pellegrini (IIT, Italy) “Graphene and other 2d crystals for energy devices”

Symposium Graphene & 2D Materials

Flavio Pendolino (University of Padova, Italy) “Temperature Influence of Production of Single and Multilayer Graphene Oxide” Alain Pénicaud (CRPP-CNRS, France) “Additive Free, Single Layer Graphene in Water & Few Graphene layers from Food Waste” Ana Perez (FUNDACION TECNALIA, Spain) “Chemical decontamination of polluted water” Inês Pinto (INL, Portugal) “INL Therapeutics: innovative systems for the induction of immunotolerance and selective cell death”

Oral Senior Parallel session

107 108

Invited Symposium Graphene & 2D Materials

Oral Senior Parallel session

109 110

Keynote Plenary Session

111

Keynote

Bernard Plaçais (LPA/ENS, France) “A fully tunable Klein tunneling contact junction in graphene”

Symposium Graphene & 2D Materials

Vladimir Popov (National University of Science and Technology "MISIS", Russia) “Development of Aluminum Matrix Composites with Non-agglomerated Nanodiamond Reinforcements ”

Danny Porath (The Hebrew University, Israel) “The Quest for Charge Transport in Single Adsorbed Long DNA-Based Molecules” Volker Rose (Argonne National Laboratory, USA) “Synchrotron X-ray Scanning Tunneling Microscopy: Elemental Fingerprinting of Materials with Sensitivity at the Atomic Limit”

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Oral Senior

112

Oral Senior Plenary Session

113

Keynote Plenary Session

114

Oral Senior Plenary Session

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TNT2015

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Speakers

TNT2015

page Federico Rosei (INRS–EMT, Univ. du Québec, Canada) “Multifunctional materials for electronics and photonics” Samuel Sanchez (IBEC, Spain) “Nano-bots as future trends in nano-bio-medicine” Olivier Sandre (Université de Bordeaux/CNRS/Bordeaux-INP ENSCBP, France) “Magnetic polymer micelles and nano-vesicles for selective cytotoxicity by magnetic hyperthermia and magnetic field-triggered drug release”

117

Keynote Plenary Session

Symposium Graphene & 2D Materials

Patrice Simon (Université Paul Sabatier, France) “Recent advances on the understanding of ion adsorption/transfer in nanoporous carbon electrodes; application to supercapacitors” Laurent Simon (IS2M-UMR7361-CNRS-UHA, France) “First Direct Observation of Diels-Alder Reactions on Graphene without Defects” José Solla-Gullón (University of Alicante, Spain) “Electrocatalysis on shape-controlled metal nanoparticles: advances and challenges” David Soriano (ICN2, Spain) “Exploring Edge Magnetism in Oxygen-terminated zigzag Phosphorene Nanoribbons” Alexander Steinman (National University of Science and Technology "MISIS", Russia) “The synthesis of BN-nanostructures from borates of alkali and alkaline-earth metals” Yoshihiko Takano (NIMS, Japan) “Crystal architecture on superconducting layered materials” Van Truong Tran (Institut d´Électronique Fondamentale (IEF), France) “Enhancement of thermoelectric properties in in-plane Graphene/BN structures” Simon Tricard (CNRS, LPCNO, INSA, Université de Toulouse, France) “Molecules affect charge transport in nano-particle self-assemblies, at room temperature” Damien Tristant (LPCNO-INSA, France) “Probing lattice temperature in current-driven carbon nanotube fibers by Raman spectroscopy” Tohru Tsuruoka (MANA / NIMS, Japan) “Operation Mechanism and Novel Functions of gapless-type atomic switches based on metal oxide and polymer thin films” Paolo Vavassori (CIC nanogune, Spain) “Magnetoplasmonic nanoantennas metamaterials: news and views” Shyam S. Venkataraman (BASF SE, Germany) “Preparation and performance of few layer graphene in energy storage applications” Kurt Vesterager Gothelf (iNANO/Aarhus University, Denmark) “DNA-Programmed Assembly of Molecules and Materials” Yutaka Wakayama (MANA / NIMS, Japan) “Molecules meet Si: bridging single-molecular function with practical device”

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Keynote Plenary Session

116

118

Keynote

Sai Shivareddy (Tata Steel, UK) “Surface engineering steel through graphene and nanocarbons”

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Keynote Plenary Session

Oral Senior Plenary Session

120 121

Oral Senior Plenary Session

122

Oral Senior Symposium Graphene & 2D Materials - Track A

123

Oral Senior Plenary Session

Keynote Plenary Session

Oral PhD Parallel session

124 125 126

Oral Senior Plenary Session

127

Oral PhD Parallel session

128

Keynote Plenary Session

129 131

Keynote Symposium Graphene & 2D Materials

Keynote Plenary Session

133 134 135

TNT2015 toulouse (france)

Symposium Graphene & 2D Materials

Irene Yarovsky (Health Innovations Research Institute, Australia) “Designing Gold Nanoparticles for Biomedical Applications: Insights from Theoretical Simulations” Marketa Zukalova (J. Heyrovsky Institute of Physical Chemistry, ASCR, Czech Republic) “Mechanism of alkali metal insertion into TiO2 polymorphs”

TNT2015 toulouse (france)

137

Oral Senior Plenary Session

138

Oral Senior Plenary Session

139

Keynote Symposium Graphene & 2D Materials

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Di Wei (Nokia-TECH/Cambridge, UK) “Graphene for energy solutions”

Amaia Zurutuza (Graphenea, Spain) Title not available

Speakers

page Keynote

TNT2015 Abstracts

DNA Origami for plasmonics and fluorescence applications

Guillermo Acuna g.acuna@tu-bs.de

TU Braunschweig, Institute of Physical and Theoretical Chemistry, Hans-Sommer-Str. 10, Braunschweig, Germany

This contribution will focus on different applications of the DNA-Origami technique [1] in the fields of plasmonics and fluorescence enhancement. In particular, we employ DNAOrigami as a platform where metallic nanoparticles as well as single organic fluorophores can be organized with nanometer precision in three dimensions. With these hybrid structures we initially study the nanoparticle-fluorophore interaction in terms of the distance-dependent fluorescence quenching [2] and angular dependence around the nanoparticle [3]. Based on these findings, we build highly efficient nanoantennas (figure a) based on 100 nm gold dimers [4-5] which are able to strongly focus light into the sub-wavelength region where the fluorophore is positioned and produce a fluorescence enhancement of more than three orders of magnitude. Using this highly confined excitation field we were able to perform single molecule measurements in solution at concentrations as high as 5 ÂľM in the biologically relevant range (>1ÂľM). Additionally, we report on a controlled increment of the radiative rate of organic dyes in the vicinity of gold nanoparticles with the consequent increment in the number of total emitted photons [6,7]. We also employ the nanoantennas to mediate the fluorophore emission and thus to shift the apparent emission origin. Finally we will discuss how DNA-Origami can also improve the occupation of other photonic structures, the zeromode waveguides (ZMWs). These structures, which consist of small holes in aluminum films can serve as ultra-small observation volumes for singlemolecule spectroscopy at high, biologically relevant

Figures

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concentrations and are commercially used for realtime DNA sequencing [8]. To benefit from the single-molecule approach, each ZMW should be filled with one target molecule which is not possible with stochastic immobilization schemes by adapting the concentration and incubation time. We present DNA origami nano-adapters that by size exclusion allow placing of exactly one molecule per ZMW (figure b). The DNA origami nanoadapters thus overcome Poissonian statistics of molecule positioning [9] and furthermore improve the photophysical homogeneity of the immobilized fluorescent dyes [10].

References [1] P. W. Rothemund, Nature 440, (2006) 297. [2] G. P. Acuna et al., ACS Nano 6, (2012) 3189. [3] F. MĂśller, P. Holzmeister, T. Sen, G. P. Acuna and P. Tinnefeld, Nanophotonics 2, (2013) 167. [4] G. P. Acuna et al., Science 338, (2012) 506. [5] G. P. Acuna et al., Journal of Biomedical Optics 18, (2013) 065001. [6] J. Pellegrotti et al., Nano Letters 14, (2014) 2831. [7] P. Holzmeister, E. Pibiri, J.J. Schmied, T. Sen, G. P. Acuna and P. Tinnefeld, Nat. Comm. 5, (2014) 5356. [8] Eid J et al., Science 323, (2009) 133. [9] E. Pibiri, P. Holzmeister, B. Lalkens, G.P. Acuna and P. Tinnefeld, Nano Letters 14, (2014) 3499. [10] S. Heucke et al., Nano Letters. 14, (2014) 391.

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Electrolyte-gated graphene field-effect transistors for biosensing applications fabricated at the wafer scale

P. Alpuim1,2, N.C.S. Vieira1,3, G.M. Junior1, M.F. Cerqueira2, N.M.R. Peres2, J. Borme1

INL – International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga, Braga, Portugal 2 CFUM – Centre of Physics, University of Minho, Campus de Gualtar, Braga, Portugal 3 GNano – Nanomedicine and Nanotoxicology Group, Physics Institute of São Carlos, University of São Paulo, São Carlos-SP, Brazil

pedro.alpuim.us@inl.int

Since the discovery of graphene more than ten years ago [1] considerable progress was made in the elucidation of its unique physical properties and in the use of these properties in the construction of useful devices. However, graphene devices designed for mass-production are lagging behind such fundamental and applied research achievements [2]. This is due in part to the difficulty in obtaining graphene over large-areas with uniform electronic properties, after suffering a transfer process that uses a polymeric temporary substrate and after being submitted to a sequence of lithographic steps for patterning.

impurities adsorbed at the graphene surface [4]. Using the results of the simulations, transistor performance parameters such as ambipolar carrier mobility, were extracted (μh ≈ μe ≈ 1850 cm2 V-1s-1). Preliminary results show that the devices are highly sensitive to changes in the channel charge environment induced by chemical and biomolecules in solution, as illustrated in Figure 1c, where antibody anti-gen bio-recognition events are transduced into changes in the position of the minimum conductivity point of the EGFET transfer curve.

In this work, we report the fabrication, operation, and modeling of a fully-integrated electrolyte-gated graphene field-effect transistor (EGFET), where the conventional wire gate electrode is replaced by an in-plane recessed metallic gate (Figure 1a). The devices are replicated 280 times in an array that covers the surface of a 200 mm oxidized silicon wafer by means of a standard UV-optical lithography clean-room process, which is rendered compatible with graphene. The proposed integrated gate geometry provides an efficient transistor gating, confines the droplet used as gate dielectric inside the transistor active zone, and provides a platform of high sensitivity for detection of chemical and biomolecules that can be dissolved in the liquid gate dielectric. The EGFET gate capacitance is a series combination of the electrical double layer capacitance of the electrolyte and the quantum capacitance of graphene. Both capacitances are comparable in size and are not readily accessible for measurement [3]. Therefore, we fitted the transistor conductivity data using a physical model that describes the dc conductivity of graphene as a function of the gate voltage (Figure 1b), based on carrier resonant scattering due to strong short-range potentials originating from

References

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[1] K.S. Novoselov; A.K. Geim; S.V. Morozov; D. Jiang; Y. Zhang; S.V. Dubonos; I.V. Grigorieva; A.A. Firsov, Science 306 (2004) 666. [2] K.S. Novoselov; V.I. Falko; L. Colombo; P.R. Gellert; M.G. Schwab; K. Kim, Nature 490 (2012) 192. [3] J. Xia; F. Chen; J. Li; N. Tao, Nature Nanotechnology 4 (2009) 505. [4] A. Ferreira; J. Viana-Gomes; J. Nilsson; E.R. Mucciolo; N.M.R. Peres; A.H.Castro Neto, Physical Review B 83 (2011) 165402.

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Figures (a)

(b)

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(c)

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New applications, effects and fundamentals in single-molecule wires

Albert C. Aragonès, 1,2, N.Darwish1, F.Sanz1,2 and I.Díez-Pérez1,2

Departament de Química Física, Universitat de Barcelona, Diagonal 645, and Institut de Bioenginyeria de Catalunya(IBEC), Baldiri Reixac 15-21, 08028 Barcelona, Catalonia, Spain 2 Centro Investigación Biomédica en Red (CIBER-BBN), Campus Río Ebro-Edificio I+D, Poeta Mariano Esquillor s/n, 50018 Zaragoza, Spain

Inspired by the proposal that single molecules will be functional parts of future nanoelectronic and photovoltaic devices, there exists a considerable interest in understanding charge transport on individual molecular backbones.[1] To investigate these nanoscale devices, a scanning tunneling microscopy in the break-junction approach (STMBJ)[2] allows us perform electrical measurements at the single molecule level. The first block of this seminar will present novel method of forming highly efficient molecular wires that hold great promise in this area. Using STM-BJ we show that when a single porphyrin molecule is wired from its metallic center, the conductivity is three orders of magnitude higher than porphyrins wired from side/contacts. This approach of wiring porphyrins mimics the natural way energy is transferred across porphyrins in photosynthetic systems and opens the door for. (Fig. 1).[3,4] For the second block, we will present a novel method to catalyze chemical reactions at the nano-scale. We have designed a surface model system to probe DielsAlder chemical reactions and the STM-BJ was used to deliver an oriented electrical field-stimulus across two reactants placed in both electrode (Fig.2). This

acortijos@ub.edu

method enable studying chemical reactions at the single-molecule level. Last topic of this contribution is about the STM not only provides a perfect voltage control between both electrodes, also offers the control of electron‘s spin using a magnetized tip. The interface magnetism or spinterface resulting from the interaction between a magnetic molecule and a metal surface as the STM electrodes, has become a key ingredient to engineering nanoscale molecular devices with novel functionalities, as a spintronic-switch (Fig. 3).

References [1] A. C. Aragonès, N. Darwish, J. Im, B. Lim, J. Choi, S. Koo, I. Díez-Pérez, Chem. - A Eur. J. 2015, 21, 7716–7720. [2] B. Xu, N. J. Tao, Science 2003, 301, 1221–3. [3] A. C. Aragonès, N. Darwish, W. J. Saletra, L. Pérez-García, F. Sanz, J. Puigmartí-Luis, D. B. Amabilino, I. Díez-Pérez, Nano Lett. 2014, 14, 4751–6. [4] I. Ponce, A. C. Aragonès, N. Darwish, P. PlaVilanova, R. Oñate, M. C. Rezende, J. H. Zagal, F. Sanz, J. Pavez, I. Díez-Pérez, Electrochim. Acta 2015, DOI 10.1016/j.electacta.2015.03.150.

Figures

Figure 1. Molecular wire through the metal.

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Figure 2. Single-molecular reactor.

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Figure 3. Fe-complex as a spintronic-switch.

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Photonic 1D nanomaterials: Correlation between Optical Properties at sub-nanometer scale with its structure at atomic scale 1 2

Jordi Arbiol1,2 , María de la Mata2 , Aziz Genç2 arbiol@icrea.cat

Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, CAT, Spain Institut Català de Nanociència i Nanotecnologia, ICN2, 08193 Bellaterra, CAT, Spain

Technology at the nanoscale has become one of the main challenges in science as new physical effects appear and can be modulated at will. Superconductors, materials for spintronics, electronics, optoelectronics, chemical sensing, and new generations of functionalized materials are taking advantage of the low dimensionality, improving their properties and opening a new range of applications. As developments in materials science are pushing to the size limits of physics and chemistry, there is a critical need for understanding the origin of these unique physical properties (optical and electronic) and relate them to the changes originated at the atomic scale, e.g.: linked to changes in (electronic) structure of the material. During the seminar, I will show how combining advanced electron microscopy imaging with electron spectroscopy, as well as cathodoluminescence in an aberration corrected STEM will allow us to probe the elemental composition and electronic structure simultaneously with the optical properties in unprecedented spatial detail.

References

[1] A. Fontcuberta i Morral, J. Arbiol, et al., Small, 4, 899 (2008) [2] M. Heigoldt, J. Arbiol,* et al., Journal of Materials Chemistry, 19, 840 (2009) [3] J. Arbiol* et al., Nanoscale, 4, 7517 (2012) [4] E. Uccelli, J. Arbiol,* et al., ACS Nano, 4, 5985 (2010) [5] M. Heiss, J. Arbiol et al., Nature Materials, 12, 439 (2013) [6] J. Arbiol,* et al., Materials Today, 16, 213 (2013) (invited Review) [7] M. de la Mata, J. Arbiol,* et al., Journal of Materials Chemistry C, 1, 4300 (2013) (invited Review) [8] E. González, J. Arbiol, V. F. Puntes, Science, 334, 1377 (2011)

The seminar will focus on several examples in advanced nanomaterials for optical and plasmonic applications. In this way the latest results obtained by my group on direct correlation between optical properties at sub-nanometer scale and structure at atomic scale will be presented. The examples will cover a wide range of nanomaterials: quantum structures self-assembled in a nanowire: quantum wells (2D),[1,2] quantum wires (1D) [3] and quantum dots (0D) [4,5] for optical applications (LEDs, lasers, quantum computing, single photon emitters) [6,7]; as well as metal multiwall nanoboxes and nanoframes [8] for 3D plasmonics.

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Figure 1. left) Sketches of different quantum structures classified by their dimensionality: (a) Quantum Wells or 2D structures (QWs); (b) Quantum Wires or 1D structures (QWRs); (c) Quantum Dots or 0D structures (QDs). (d-f) Experimental STEM and HRTEM images of the quantum structures, QWs, QWRs and QDs, respectively [6,7]. (right) Subnanometer Plasmon analysis on a 3D Au/Ag nanobox.

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Non-covalent Functionalization of Carbon Based Nanostructures and Its Application to Carbon/Epoxy Composites

Antonio F Avila, Viviane C. Munhoz, Nathalia Menezes, Suchilla G. LeĂŁo, Camila F. da Silva

avila@demec.ufmg.br Universidade Federal de Minas Gerais, 6627 Antonio Carlos Avenue, Belo Horizonte, Brazil

The purpose of this research is to investigate the effect of non-covalent functionalization by the usage of surfactant addition on carbon/epoxy composites nano-modified by carbon nanotubes (MWCNT) and graphene (MLG). To achieve this goal, a series of 36 hybrid composite materials were prepared, tested and analyzed. The amount of MWCNT and MLG employed in this research were 0.15% wt and 0.30% wt. The surfactants (Polyoxyethylene (40) nonylphenyl ether - IGEPALÂŽ CO-890 and Sodium dodecylbenzenesulfonate - SDBS) were selected based on Tkalya et al. [1] results. AS described by Lee et al. [2], the tensile test follows the ASTM D3039 standard, while the three point bending test followed the ASTM D790 standard. The macroscopic analysis based on bending and tensile tests were analyzed first. Stiffness and strength were the two key parameters evaluated. When the carbon/epoxy nano-modified composite macro mechanical behavior is analyzed some comments can be drawn. First, the usage on ionic surfactants (SDBS), which is commonly used to disperse carbon nanotubes, has no significant effect into the CNT-epoxy system interaction. On the other hand, the non-ionic surfactant (CO890) seems to be effective to the graphene-epoxy and/or the graphene-CNT-epoxy systems. Based on tensile tests (Fig. 1A) and increase on stiffness around 9.45% was observed due to the usage of CO890 and MLG in addition to the pristine MWNT. A much higher increase was detected on ultimate strength, i.e. 23.49%. For the bending analysis (Fig. 1B), no significant change on flexural stiffness was observed; in fact for some groups (27 and 33) a decrease was detected. An average increase on bending ultimate strength of approximately 11.44% was notice for the specimens with MLG+CO890 and pristine MWNT (group 19). Again the linkage by tail for graphene and head for carbon nanotube can be the reason for such behavior. Note that Figures 2A-B show the nanostructures dispersion in a three-dimensional for

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samples from group 25 and 19, respectively. These nanostructures seem to provide the extra grip for energy dissipation and the increase on ultimate strength for tensile and bending tests.

References [1] Tkalya, E., Ghislandi, M., de With, G., Koning, C.E. Current Opinion in Colloid & Interface Science, 17 (2012) 225. [2] Lee, S.H., Lee, D.H., Lee, W.J. and Kim, S.D., Advanced Functional Materials, 21 (2011), 1338.

Figures

Figure 1. Stress-strain curves. (a) Tensile; (b) Bending

Figure 2. AFM representation (a) sample from Group 25; (b) sample from Group 19

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What is the difference between a graphene mechanical resonator and a music drum?

Adrian Bachtold adrian.bachtold@icfo.es

ICFO â&#x20AC;&#x201C; The Institute of Photonic Sciences, Castelldefels (Barcelona), Spain

When a graphene layer is suspended and clamped over a circular trench, the graphene acts as a drum. Likewise, a suspended nanotube vibrates in way similar to a guitar string. However, one difference is the mass, since graphene is only one atom thick, and the diameter of nanotubes is about 1 nm. Another difference is that the quality factor Q becomes extremely large at cryogenic temperature, up to 5 million [1]. This large Q-factor reflects the high crystallinity of graphene and nanotubes and their lack of dangling bonds at the surface. Because of this combination of low mass and high quality factor, the motion is enormously sensitive to the environment - the mechanical eigenstates are extremely fragile and easily perturbed by the measurement. But, if graphene and nanotube resonators can be properly harnessed, they become incomparable sensors of mass [2] and force [3].

References [1] J. Moser, A. Eichler, J. GĂźttinger, M. I. Dykman, A. Bachtold, Nature Nanotechnology 9, 1007 (2014). [2] J. Chaste, A. Eichler, J. Moser, G. Ceballos, R. Rurali, A. Bachtold, Nature Nanotechnology 7, 301 (2012). [3] J. Moser, J. GĂźttinger, A. Eichler, M. J. Esplandiu, D. E. Liu, M. I. Dykman, A. Bachtold, Nature Nanotechnology 8, 493 (2013).

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Important impact of the experimental platform on the efficient simultaneous control of electronic and vibrational properties of molecular junctions

Ioan Bâldea

ioan.baldea@pci.uni-heidelberg.de

Theoretische Chemie, Universität Heidelberg, INF 229, D-69120 Heidelberg, Germany

A recent work [1] reported on simultaneous surface enhanced Raman scattering (SERS) and transport current-voltage I-V measurements in electromigrated molecular junctions based on fullerene C60. In molecular junctions, the SERS is observable because of the enormous electromagnetic enhancement near sharp metallic electrodes (tips), which act as highly efficient plasmonic antennas [2]. Vibrational frequencies measured in Ref. 1 were found to be slightly but significantly shifted by the applied bias V. Companion DFT calculations indicated that these Vdriven shifts cannot be due to a simple vibrational Stark effect but are compatible to a partial reduction of the C60 molecule, whose lowest unoccupied molecular orbital (LUMO) becomes partially occupied under bias. The V-values used in experiment turned out to be far less than needed for adding en entire electron to the molecule. In this context, one of the questions addressed here is whether the experimental platform of Ref. 1 represents the most favorable setup to achieve a(n almost) complete bias-driven reduction [3]. The answer [3] is that (i) no matter how high the voltage is, reduction cannot exceed 50% in an experimental setup (like that of Ref. 1) where the molecule is symmetrically coupled to the (source and drain) electrodes, (ii) reduction can be almost complete in cases of highly asymmetric moleculeelectrode couplings, but in this case (iii) biases corresponding to current plateaus are required, which common junctions cannot withstand. We next discuss that, much more than in twoterminal setups, the molecular charge, orbital energies, and vibrational properties can be efficiently controlled in case of (redox) molecules embedded in scanning tunneling microscope (STM) junctions in electrochemical (EC) environment [4]. The electrochemical setup provides a unique chance to control the molecular properties. The key role in the unprecedented efficiency of this control is played by the electrolyte gating, which enables a

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continuous change in the molecular charge by up to an entire electron (complete redox process). To exemplify, we consider EC-STM experimental transport data for the redox unit (viologen) [5], whose essential constituent is 4,4’-bipyridine (44BPY), a molecule of special interest for the charge transport at the nanoscale, on which we focused in a series of recent studies [6,7,8,9,10]. The relevant redox process is between the oxidized (44BPY++) and the reduced (44BPY+.) species. Obviously, to observe changes in vibrational properties of the kind mentioned above, the vibrational properties of the oxidized and reduced species must significantly differ. Fig. 1 depicts that this is indeed the case for the EC-STM junctions considered here.

References [1] [2] [3]

Y. Li et al, Proc. Natl. Acad. Sci. 111 (2014) 1282. P. Mühlschlegel et al, Science 308 (2005) 1607. I. Bâldea, Phys. Chem. Chem. Phys. Advance Article, DOI: 10.1039/C5CP01805F [4] I. Bâldea, Phys. Chem. Chem. Phys.16 (2014) 25942. [5] I. V. Pobelov, Z. Li, and T. Wandlowski, J. Am. Chem. Soc. 130 (2008) 16045. [6] I. Bâldea, Nanoscale 5 (2013) 9222. [7] I. Bâldea, Faraday Discussions 174 (2014) 35. [8] I. Bâldea, H. Köppel and W. Wenzel, Phys. Chem. Chem. Phys. 15 (2013) 1918. [9] I. Bâldea, Electrochem. Commun. 36 (2013) 19. [10] I. Bâldea, J. Am. Chem. Soc. 134 (2012) 7958.

Figures

Figure 1. Raman spectra of the dicationic and cationic species of bipyridine exhibit substantial differences. Notice the logarithmic scale on the ordinate axis.

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Synthesis of InP/ZnS Nanocrystals Under Mild Conditions UniversitĂŠ de Toulouse; INSA, UPS, CNRS; LPCNO (Laboratoire de Physique et Chimie des Nano-Objets), 135 avenue de Rangueil, F-31077 Toulouse, France

The synthesis of InP Quantum Dots (QDs) under mild conditions remains a challenge in nanochemistry. Recently, we have demonstrated that the use of classical high-temperature procedure, following the protocol reported by Peng and co-workers (Scheme 1a),[1] promotes decarboxylation processes of the stabilizers (fatty carboxylic acids) as side reactions. Concomitant formation of water oxidized the surface of the particles and therefore, inhibited their growth.[2,3] The original strategy presented here consists in the use of a highly reactive indium precursor such as In(amidinate)3 complex, which in the presence of P(SiMe3)3 as phosphorous source and both hexadecylamine (HDA) and palmitic acid (PA) as stabilizers, leads to the formation of InP nanocrystals at lower temperatures (Scheme 1b), followed by a shelling process with ZnS insuring the air stability of the QDs(Scheme 1c). This unprecedented methodology at low temperature avoided the undesired reactions above mentioned, leading to the formation of non oxidized InP QDs. We observed the presence of oxides at the surface

Edwin A. Baquero, WilfriedSolo Ojo, Angelique Gillet, Bruno Chaudret, Fabien Delpech and CĂŠline Nayral ebaquero@insa-toulouse.fr

after the ZnS coating process, and our findings showed that it is mainly due to an amidation process, which is taking place with formation of water. Thus, different oxidative conditions due to side-reactions have been identified and the possibilities to avoid the QDs surface oxidation by using low temperatures or a reductive atmosphere will be exposed. The QDs were fully characterized by TEM, and spectroscopic techniques such as UVVis, Photoluminescence Spectroscopy, and solution and solid state 1H, 13C, 31P NMR techniques.

References [1] D. Battaglia, X. Peng, Nano Letters, 2 (2002) 1027. [2] A. Cros-Gagneux, F. Delpech, C. Nayral, A. Cornejo, Y. Coppel, B. Chaudret, J. Am. Chem. Soc., 132 (2010) 18147. [3] H. Virieux, M. L. Troedec, A. Cros-Gagneux, W. Solo-Ojo, F. Delpech, C. Nayral, H. Martinez, B. Chaudret, J. Am. Chem. Soc., 134 (2012) 19701.

Figures

Scheme 1. Synthesis of 1a) InP QDs developed by Peng and co-workers.[1] 1b) InP QDs described in this work and 1c) Coating process of InP QDs with ZnS.

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Graphene and 2D materials in the perspective of a global energy player

Laurent Baraton, Louis Gorintin and Tanguy Leveder

CCRIGEN Nanotech Energy – Research & Technology Division - Engie. 361, av. Pdt Wilson – BP 33 – 93211 Saint Denis La Plaine Cedex – France

laurent.baraton@external.gdfsuez.com

As a major energy player Engie develops its businesses (power, natural energy and energy services) around a model based on responsible growth to take up today’s major energy and environmental challenges: meeting energy needs, ensuring the security of supply, fighting against climate change and maximizing the use of resources. Innovation is a key assets to achieve this development and as one of the most active domain of research and development, nanotechnologies are a useful part of the toolset at hand. Furthermore, long awaited large scale commercial applications of nanomaterials and nano-objects start to appear and real improvements in performances and/or costs are observed (figure 1). In that perspective, this talk will try to give an overview of the potential application of graphene that may quickly find usefulness in the energy industry. At first, we will look at the development of graphene based devices for energy storage, energy transformation through catalytic processes and energy harvesting. Then we will try to assert the impact of graphene based electronics on the development of smart energy network, from sensors and actuators to low energy consumption devices that allow local process or transmission of the collected data. Finally, we’ll expose through which processes and framework an international industrial group such as Engie can become an early adopter of such emerging technologies.

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Figure 1. Commercial products that rely on nanomaterials or nano-objects: From left to right: SUHD TV from Samsung (Quantum dots), light bulb from Graphene Lightning PLC and handheld supercapacitor from Zap&Go (Graphene).

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Preparation and characterization of carbon nanoonions modified electrodes for biosensor applications Nanobiotechnology & Bioanalysis Group, Departament d’Enginyeria Química Universitat Rovira i Virgili, Avinguda Països Catalans 26, 43007 Tarragona, Spain

Carbon nanoonions (CNOs) are multilayered fullerenes concentrically arranged one inside the other that can be prepared using different carbon precursors.[1-2] Although they have been less studied as compared with other carbon allotropes such as nanotubes and graphene, they possess interesting properties such as higher surface area and improved electronic properties. Moreover, to exploit the inherent electrochemical properties of CNOs, they have been chemically functionalized or incorporated in composites [3-6]. Here we report the preparation of CNOs by thermal annealing of nanodiamonds and their incorporation in glassy carbon electrodes (GCEs) followed by electrochemical grafting of diazonium salts bearing carboxylic acid or maleimide terminated groups. The modified surfaces were used for the design of amperometric genosensors and immunosensors. Briefly, the DNA sensor has been developed using human papilloma virus (HPV) model system with horseradish peroxidase (HRP)- as labelled probe, whereas, an IgG sensor used alkaline phosphatase (ALP) as labelled probe. Both of the systems with modified GCE/CNOs showed enhanced analytical performance such as lower limit of detection and higher sensitivity as compared to non-modified GCEs. They were also tested in real samples.

Joanne P. Bartolome and Alex Fragoso

joanne.pinera@urv.cat

References [1] V. L. Kuznetsov, A. L. Chuvilin, Y. V. Butenko, I. Y. Mal'kov, V. M. Titov, Chemical Physics Letters,222 (1994) 343-348. [2] J.Cebik, J.K.McDonough, F.Peerally, R.Medrano, I. Neitzel, Y.Gogotsi, S. Osswald, Nanotechnology, 24 (2013) 205703. [3] J. Breczko, K. Winkler, M.E. Plonska-Brzezinska, A. Villalta-Cerdas, L. Echegoyen, Journal of Materials Chemistry, 20 (2010) 7761-7768. [4] M.E. Plonska-Brzezinska, J. Mazurczyk, B. Palys, J. Breczko, A Lapinski, A.T. Dubis, L. Echegoyen,Chemistry a European Journal, 18 (2012) 2600-2608. [5] M.E. Plonska-Brzezinska. M. Lewandowski, M. Blaszyk, A. Molina-Ontoria, T. Lucinski, L. Echegoyen, CHEMPHYSCHEM, 13 (2012) 41344141. [6] J. Luszczyn, M.E. Ploska-Brzezinska, A. Palkar, A.T. Dubis, A. Simionescu, D.T. Simionescu, B. KalskaSzostko, K. Winkler, L. Echegoyen,Chemistry a European Journal, 16 (2010) 4870-4880.

Figures

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Targeting the Tumor Microenvironment with Polymeric Nanomicelles

Ofra Benny ofrab@ekmd.huji.ac.il

Institute for Drug Research, Faculty of Medicine The Hebrew University of Jerusalem, Jerusalem Israel

Angiogenesis, the formation of new blood vessels, is a multifactorial process that is critical for tumor progression and metastasis. Anti-angiogenic compounds, has been widely investigated as a strategy to treat cancer. However, several of these drugs are limited by poor pharmacological properties, such as low bioavailability, undesired biodistribution and short half-life necessitating their use in high intravenous doses which expose the patients to adverse size-effects due to off target activity. To overcome these drug limitations, we developed a formulation of self-assembled nanomicelles composed of short di-block polymers, polyethylene glycol-polylactic acid (PEG-PLA), for conjugating small molecule drugs. We present a case of re-formulating a broad spectrum anti-

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angiogenic drug from the fumagillin family which originally had several clinical limitations. In the new formulation, unlike the free compound, the drug showed high oral availability, improved tumor targeting and reduced toxicity. Dramatic anti cancer activity was obtained in eight different tumor types (60-90% growth inhibition) in mice, and, importantly, the treatment was able to prevent liver metastases due to the shift from intravenous to oral administration. The activity was associated with reduction of microvessel density and increased tumor apoptosis. Nanomicelle drug delivery system has been shown to be an efficient approach for improving pharmacological properties of drugs and is now being studied as multi-drug carrier.

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Magnetic field-induced supracolloidal assemblies for micro-rheology applications

J.-F. Berret

jean-francois.berret@univ-paris-diderot.fr

Matière et Systèmes Complexes, UMR 7057 CNRS Université Denis Diderot Paris-VII Bâtiment Condorcet 10 rue Alice Domon et Léonie Duquet, 75205 Paris (France)

The emergence of novel materials and processing at the nanoscale has set the conditions for the fabrication of a wide range of nano-objects and multilevel nanostructured networks. In this communication we report a simple and versatile waterborne synthesis of magnetic nanowires following the innovative concept of electrostatic ‘’desalting transition’’. Highly persistent superparamagnetic nanowires are generated from the controlled assembly of oppositely charged nanoparticles and polymers [1]. The particles considered for the assembly are 10 nm iron oxide particles. The wires have diameters of 200 nm and lengths comprised between 1 mm and 1/2 mm. The wires are rigid and able to reorient via the application of a magnetic field. In a second part, the

nanowires are tested as probes for microrheology experiments. The mechanical responses of the complex fluids (Figure 1) and of the intracellular medium of cells is presented and compared to that of model viscoelastic liquids [2,3].

References [1] Fresnais, J.; Berret, J.-F.; Frka-Petesic, B.; Sandre, O.; Perzynski, R., Adv. Mater. 20 (2008) 3877 –3881. [2] L. Chevry, R. Colin, B. Abou and J.-F. Berret, Biomaterials 34 (2013) 6299 – 6305 [3] R. Colin, L. Chevry, J.-F. Berret and B. Abou, Soft Matter 10 (2014) 1167–1173

Figures

Figure 1. Images of a 9.2 μm long wire immersed in a wormlike micellar solution at c = 1 wt. %; (b): Time dependence of the orientation angle ϕ(t). (c): Rotational diffusion coefficient versus length forwires dispersed in a water/glycerol solution (labeled Newton fluid) and in micellar solutions (labeled Maxwell fluids). The rotational diffusion coefficient 3 varies as 1/ߟ‫ ܮ‬, as indicated by the continuous lines, where L is the length of the wire and ߟ the static viscosity.

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Ultra-dense array of singlecrystalline cobalt nanowires 1

Laboratoire de Physique et Chimie des Nano-objets, UMR5215, INSA, Toulouse, France IPCMS, UMR7504 CNRS-Université de Strasbourg, 67034 Strasbourg, France

Up to now, ferromagnetic nanowires (NWs) were mainly synthesized by electrodeposition of metals in nanoporous templates resulting in polycrystalline NWs of relatively large diameters and packed at moderate densities. Recently, we reported the epitaxial solution growth of single-crystalline hcp Co nanowires of 6 nm in diameter. Without any template, they grow vertically on a un-patterned 1×1 cm2 Pt(111) film (Fig.a), are spontaneously arranged in hexagonal arrays of 1012 NWs/cm2 and present a perpendicular anisotropy at room temperature [1]. These properties confer a high interest of this system in future ultrahigh magnetic recording. We present here a detailed magnetic study of such a Co NW array in terms of coercivity, dipolar interactions and magnetocrystalline anisotropy. Despite important dipolar interactions, a high perpendicular anisotropy (i.e. parallel to the wires) is obtained due to the combination of the Co hcp magnetocrystalline and shape anisotropies which both act along the wire axis: at 300 K, the anisotropy is Keff = 2.4×105 J/m3 with a coercive field µ0HC = 0.35 T and remanence value Mr/Ms=0.61 (Fig.b). This coercive field reaches 0.62 T at 4 K, without any Co/Co oxide exchange bias effect after field cooling. This demonstrates that the chemical synthesis produces intrinsically oxygen free Co nanowires. Contrary to electrodeposited nanowires, the measured temperature dependence of Hc cannot be explained by the Sharrock formula deduced from Stoner-Wohlfarth and Néel-Brown models. On the other hand, the angular dependence of HC suggests a coherent rotation of the magnetization. The easy

T. Blon1, N. Liakakos1, C. Achkar1, I. Camara2, M. Bailleul2, C. Meny2, V. Pierron-Bohnes2, Y. Henry2, B. Chaudret1, K. Soulantica1, M. Respaud1 thomas.blon@insa-toulouse.fr

axis hysteresis loops are sheared due to dipolar interactions (Fig.a) with a M(H) slope related to the demagnetizing field of the assembly. In this system, the demagnetizing factor is expected to be the array packing fraction P. We found a good agreement between the demagnetizing field slope and P=0.38 determined by small angle neutron scattering. Also, ferromagnetic nuclear resonance (FNR) measurements indicate a shift in the Co spectra related to the assembly demagnetizing field, here also in accordance with the measured packing fraction. In an alternative approach to understanding the anisotropy in this system, we used ferromagnetic resonance (FMR). We observe unusually large resonance frequencies (40 GHz at remanence) and resonance fields (2.3T hard-axis saturation field) which we attribute to an enhanced magnetocrystalline anisotropy. By modelling the dipolar interaction in the array, we could indeed reproduce the resonance positions (Fig.c) assuming a uniaxial anisotropy with first and second order constants K1=750 kJ/m3 and K2=150 kJ/m3, two values that are about 50% larger than those of bulk hcp cobalt. High-field magnetic torque measurements confirm this behaviour and give comparable values. This enhancement of the magnetocristalline anisotropy is discussed in terms of magneto-elastic effect and/or surface anisotropy.

References [1] N. Liakakos, Nano Lett. 14 3481 (2014)

Figures

Figure 1. a) TEM micrograph of a Co NW array grown on Pt(111)/Al2O3(0001). (b) Magnetic hysteresis loops measured for a magnetic field applied along the NW, i.e. the easy axis of magnetization. (c) FMR resonance frequencies as a function of the applied DC magnetic field (dots: measurements, lines: model).

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TNT2015 toulouse (france)

Non-destructive, large-area electrical characterization of graphene: a new light on defects

P. Bøggild1,2, J. D. Buron1,2, F. Pizzocchero1,2, B.S. Jessen1,2, A. Zurutuza4, A. Centeno4, A. Pesquera4,T. Booth1,2, O. Hansen2, P. U. Jepsen3 and D H. Petersen1,2

CNG – Center of Nanostructured graphene, DTU Nanotech, Technical University of Denmark 3 DTUFotonik, Technical University of Denmark 4 Graphenea

peter.boggild@nanotech.dtu.dk

We overview recent progress in fast, nondestructive large-area mapping techniques based on terahertz time domain spectroscopy (THz-TDS) and micro-four point probes [1] allowing spatial analysis of electrical continuity, carrier mobility and carrier density across up to 4’’ graphene films (see Fig. 1), as well as insights into the scattering dynamics. At low frequencies (0.1-1.5 THz) the real part of the complex conductivity derived from the THz transmittance can be approximated to the DC conductivity, with the spatial resolution limited by the THz wavelength of 0.2-3.0 mm [1]. The conductivity maps obtained with THz-TDS are in close agreement with scanning micro four point probe measurements. Transferring graphene to substrates with a THz-transparent) backgate, allows the field effect conductance and thus carrier mobility and density to be mapped as well. A deeper insight into the scattering dynamics is achieved by ultra-broadband THz-TDS up to 15 THz. While the complex conductivity of graphene grown on single crystal Cu(111) and transferred with a reusable-catalyst transfer process [2] is perfectly fitted by Drude model (isotropic scattering), graphene grown on commercial Cu foil and transferred by sacrificial Cu etching could only be described by assuming some degree of backscattering from line-defects such as grain boundaries or cracks [1,3]. The same trend was observed on the microscale using micro four point probes, using the novel dual configuration approach to analyse the defect landscape [3]. Finally we discuss recent indications that carrier density and mobility can be mapped across large areas (4” films) with THz-TDS, even without a backgate.

TNT2015 toulouse (france)

References [1] J. Buron et al, Nano Lett., 12, (2012) 5074-81 [2] F. Pizzocchero et al, Carbon, vol 85, (2015) 397-502 [3] J. D. Buron, F. Pizzocchero et al, Nano Lett., 14 11 (2014) 6348

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Figure 1. A. Direct comparison between THz-TDS and scanning 4-point conductivity maps. B. Large area conductivity and carre mobility maps. C. Analysis of frequency dependent conductivity to reveal Drude or non-Drude scattering in grapheme grown on different substrate types.

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Charge transport through functionalized multiwall carbon nanotubes

R. Bonnet1, C. Barraud1, M-L. Della Rocca1, P. Martin2, J-C. Lacroix2 & P. Lafarge1

romeo.bonnet@univ-paris-diderot.fr

Université Paris Diderot, Sorbonne Paris Cité, MPQ, UMR 7162, CNRS, Paris, France 2 Université Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086, CNRS, Paris, France

Carbon-based nanostructures [1] are promising for integration in future quantum electronic devices. It has been shown that the spin diffusion length in such materials is large enough to be suitable for storing or propagating spin information [2,3]. Both in carbon nanotubes (CNT) and graphene, experiments highlighted long spin diffusion lengths (>50μm) but there exists strict conditions about contact resistances for injecting efficiently spins from a ferromagnet to the nanotube. An experimental way to achieve efficient spin injection is to intercalate a tunnel barrier. We study the role of a molecular tunnel barrier for this system. We characterize multiwall CNT whose external shell is functionalized with organic molecules (BisThienyl-Benzene, Nitro-Benzene-Diazonium). Our chemical functionalization process is an in-solution covalent grafting process based on diazonium radicals [4]. By forming a stable C-C bond with the molecule, the carbon atoms of the outer shell change their sp2 configuration into a sp3, changing the electronic properties of the outer shell [5] and pushing the electrons towards the inner shells, which properties are usually not probed. In order to study the influence of this functionalization on charge transport properties, we performed electrical experiments at low temperatures.

References [1] Charlier, J. C., Blase, X. & Roche, S., Electronic and transport properties of carbon nanotubes. Rev. Mod. Phys.79, 677 (2007) [2] Dediu, V. A., Hueso, L. E., Bergenti, I. & Taliani, C. Spin routes in organic semiconductors. Nat. Mater. 8, 707–16 (2009). [3] Seneor, P. et al. Spintronics with graphene. MRS Bull. 37, 1245–1254 (2012). [4] Dyke, C. A., Stewart, M. P., Maya, F. & Tour, J. M. Diazonium-Based Functionalization of Carbon Nanotubes: XPS and GC-MS Analysis and Mechanistic Implications. Synlett 2004, 155–160 (2004). [5] Sun, Y. P., Fu, K., Lin, Y. & Huang, W., Functionalized carbon nanotubes: properties and applications. Acc. Chem. Res. 2002, 35 (12), pp 1096–1104

In this talk we will, in a first part, describe the fabrication process illustrated with an AFM study of the different interfaces (nanotube/molecules and ferromagnetic/molecules on nanotubes). Then, we will present transport experiments on bare and functionalized nanotubes, and discuss about the role of the molecular barrier on the electronic transport properties (injection and propagation).

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Investigating vector local field on optical nanostructure by phase-locked polarization-resolved near-field coherent imaging 1 2

G. Calbris1, M. Mivelle1, M.F. Garcia-Parajo1,2 and N.F. van Hulst1,2

gaetan.calbris@icfo.es

ICFO, Mediterranean Technology Park, 08860 Castelldefels, Barcelona, Spain ICREA, 08010 Barcelona, Spain

By squeezing optical fields down to the nanoscale, nanophotonics devices allow engineering of the light-matter interactions and thus can challenge technological limits for a broad range of applications. Governed by it vectorial nature, a specific nanostructured electric and magnetic nearfield arrangement is induced on such devices and be seen as the key enabling efficiency and functionality. Here, we present direct near-field imaging on inverted gap nanoantenna at visible wavelength (figure 1a). A near-field scanning optical microscope coupled with a polarization-sensitive interferometric detection provides direct access to quantitative amplitude and phase of the in plane near-field components (figure 1b). For the first time, simultaneous and synchronous detection of both near-field components are performed revealing their apparent phase relation [1]. The electric and magnetic nature of the detected field by such aperture probe is shown regarding the specific spatial distribution of their components phase relation [2]. Based on these phase-locked polarization-resolved coherent mappings, vector local field spatial distribution of the optical antenna

is reconstructed and it collective time evolution retrieved. The spatial and temporal structure of the localized field engendered by the narrow gap antenna when squeezing down the field to the nanoscale is highlighted. Accessing and understanding electric and magnetic field properties directly on nanophotonic structure is crucial, supporting progress in near-field engineering to manipulate light at the nanoscale.

References [1] G. Calbris, M. Mivelle, M.F. Garcia-Parajo and N.F. van Hulst in preparation. [2] B. le Feber, N. Rotenberg, D.M. Beggs and L. Kuipers, Nature Photonics 8 (2014) 43.

Figures

Figure 1. a) SEM picture of the bowtie nanoaperture optical antenna. Scale bar is 200nm. b) Experimental mapping giving four lobes pattern for the field component perpendicular to the gap mode, amplitude (z axe) and phase (map color). Scan size is 2Îźmx2Îźm.

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Gold Nanoparticles Work as the Beta-emitter to Treat Brain Tumor Institute of Biomedical Engineering & Nanomedicine, National Health Research Institute, 35 Keyan Road, Zhunan, Miaoli County 35053, Taiwan

Brain tumor therapy is extremely stringent because of very poor prognosis and limited advances of therapeutics. Concurrent chemo-radiotherapy (CCRT) has been employed for patients who have received maximal surgical resection to prohibit tumor recurrence. However, there is an offtherapeutic gap after surgery and before CCRT. In this work, gold nanoparticles (GNP) work as the beta-emitter and show the merit of loco-regional treatment to complement current protocol of brain tumor therapy. The unique nano-sized beta-emitter was prepared in a nuclear reactor without participation of reducing agents and radioactive precursors. Trivalent gold ions (Au3+) were reduced into GNP in which particular portion of natural gold atoms (197Au) were simultaneously converted into radioactive gold (198Au) atoms through a onepot/one-step reaction. The 198Au-incorporated gold nanoparticle (198Au-GNP) renders GNP extraordinary physical properties and provides multimodality to benefit patients bearing brain tumor. Firstly, the fluidic 198Au-GNP is feasible to be delivered through intracranial injection for interstitial radiotherapy. Furthermore, simultaneous emission of beta particles (Emax: 0.96 MeV) and gamma rays (412 keV) provide the niche

Jen-Kun Chen, Wei-Neng Liao, Sih-Yu Chen, ChienHung Chen

jkchen@nhri.org.tw

for killing tumor cells and tracking 198Au-GNP in vivo. The 198Au-GNP also demonstrates striking property of X-ray contrast for computed tomography (CT), which is useful to evaluate the distribution of GNP in the micro-environment of brain. We first report the application of 198Au-GNP to effectively suppress orthotopic brain tumor using positron emission tomography (PET) imaging. Significant results give us an insight into harnessing nuclear energy for preparing multimodality GNP; and further, highlight its potential for brain tumor therapy.

References [1] Chen, C.H., Lin, F.S., Liao, W.N., Liang, S.L., Chen, M.H., Chen, Y.W., Lin, W.Y., Hsu, M.H., Wang, M.Y., Peir, J.J., Chou, F.I., Chen, C.Y., Chen, S.Y., Huang, S.C., Yang, M.H., Hueng, D.Y., Hwu, Y., Yang, C.S. & Chen, J.K., Analytical Chemistry, 87 (2015) 601-608. [2] Lin, F.S., Chen, C.H., Tseng, F.G., Hwu, Y., Chen, J.K., Lin, S.Y. & Yang, C.S., International Journal of Materials, Mechanics and Manufacturing, 1 (2013) 265-268.

Figures

198

Figure 1. Using PET/CT imaging to evaluate orthotopic glioblastoma-bearing rats treated by Au-GNP. (TT: tumor treated, 198 TS: tumor sham, CT: computed tomography, PET: positron emission tomography, red arrow: implanted Au-GNP

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A fast operation of nanometer–scale metallic memristors: highly transparent conductance channels in Ag2S devices Department of Physics, Budapest University of Technology and Economics, Hungary

Since the pioneering experiments reported on AgAg2S-Pt memristor junctions [1] the development of memory cells based on memristive systems has achieved a remarkable progress. The results are extremely promising for the short term realization of highly integrated information storage applications [2]. However, due to fundamental RC limitations in the presence of the large OFF state resistances, the best performing Ag2S devices were operated up to ~10 MHz frequencies so far. Here we demonstrate a proof-of-principle memory cell which is both small (close to atomic sizes) and fast (GHz operation) [3]. We studied the resistive switching of Ag–Ag2S–Me memristive nanojunction devices. We showed that by suitable sample preparation reproducible resistive switching and readout can be performed where both the ON and OFF states are metallic, characterized by technologically optimal 100 – 1000 Ω resistances and similar device functionalities down to cryogenic temperatures. We introduced point contact Andreev reflection spectroscopy to determine the size and transmission probabilities of

Miklós Csontos, Ágnes Gubicza, Attila Geresdi, András Halbritter, György Mihály

csontos@dept.phy.bme.hu

the active volume of the devices which revealed a small number of highly transmitting nanoscale conducting channels with reduced but not completely dissolved junction area in the OFF state. The relatively low resistance ON and OFF states enable fast operation: our devices can be switched by nanosecond voltage pulses at room temperature. The achieved ROFF/RON ratios of 2 – 10 satisfy the basic requirement of reliable read-out. These results indicate that Ag2S represents a promising material basis for a future generation of high speed resistive switching memory devices overriding the downscaling limitations of current CMOS technology.

References [1] [2]

K. Terabe at al., Nature 433 (2005) 47. J.J. Yang et al., Nature Nanotechnology, 8, (2013) 13. [3] A. Geresdi, M. Csontos, A. Gubicza, A. Halbritter, G. Mihály, Nanoscale, 6 (2014) 2613.

Figures

Figure 1. Resistive switching taking place at nanosecond timescales in the Ag2S layer are attributed to a change in the diameter of the metallic conducting channel.

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Theoretical investigation for FischerTropsch reaction with metal nanoparticles: building a relevant structural model, a mandatory prerequisite

Lucy Cusinato, Iker del Rosal, Romuald Poteau

lucy.cusinato@insa-toulouse.fr

LPCNO, 135 Avenue de Rangueil, 31077 Toulouse, France

The Fischer-Tropsch synthesis is a widely known catalytic reaction that converts carbon monoxide and hydrogen into liquid hydrocarbons: Usually achieved within heterogeneous catalysis [1], nanocatalysts have also proven to be of interest as their special structural and electronic properties enhance their catalytic activity for Fischer-Tropsch synthesis as well as for a large range of reactions [2]. From the theoretical point of view, the study of such reactions implies the understanding of the nanocatalyst surface steric and electronic effects in order to be able to design relevant models usable as starting point for reactivity studies. We propose several tools in order to achieve such design: (i) molecular builder aiming at providing a wide variety of the typical shapes exhibited by nanoparticles, completed by the steric-driven grafting of ligands on its surface; (ii) reverse Monte-Carlo modeling, a general method that provides atomic structures based on experimental X-Ray or neutron diffraction data; (iii) ab initio thermodynamics [3], with the example of the adsorption and co-adsorption of dihydrogen and CO on ruthenium nanoparticles. Ab initio thermodynamics applied to hydrogenated ruthenium surfaces show a maximum coverage of 1H/Rusurface[4]. The same methodology applied to

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hydrogenated ruthenium nanoparticles evidence a larger saturation coverage (see figure below), in agreement with experimental observations [5]. Calculations on nanoparticles with coadsorbed CO and H give insight on the H/CO coverage under experimental conditions and therefore allows to perform reactivity studies on realistic models of nanocatalysts. This computational strategy examplified in the case of ruthenium nanoparticles for the Fischer-Tropsch reaction can be applied to any metallic nanoparticle.

References [1] S. Shetty, R. A. van Santen, Catalysis Today, 171 (2011) 168. [2] G. A. Somorjai, J. Y. Park, Angew. Chem. Int. Ed., 47 (2008) 9212; X.Quek, Y. Guan, R. A. van Santen, E. J. M. Hensen, Chem. Cat. Chem., 3 (2011) 1735. [3] K. Reuter and M. Scheffler, Phys. Rev. B, 65 (2001) 35406. [4] I.del Rosal, L. Truflandier, R. Poteau, and I. C. Gerber., J. Phys. Chem. C, 115 (2011) 2169. [5] J. Garcia-Anton, M. R. Axet, S. Jansat, K. Philippot, B. Chaudret, T. Pery, G. Buntkowsky, and H.-H. Limbach, Angew. Chem. Int. Ed., 47(2008) 2074.

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Dynamic and hybrid materials. Properties and applications Institute de Science et d'Ingénierie Supramoléculaires (I.S.I.S.), Université de Strasbourg and KIT Germany

Dynamic systems that can undergo reversible processes are of great interest for the development of new materials, sensors, biolabels…. The talk will illustrate some of the recent results on soft structures based on metal complexes able to aggregate in fibers, gels and soft mechanochromic materials [1]. The use of platinum complexes as building block for luminescent reversible piezochromic and mechanochromic materials will be illustrated. The emission of the compounds can be tuned by an appropriate choice of the coordinated ligands as well as of their aggregation in different structures. The formation of soft assemblies allows the tuning of the emission color, by pressure and temperature leading to a new class of materials possessing reversible properties.

Luisa De Cola

decola@unistra.fr

Acknowledgements: The authors thank ERC grant award (grant number 2009-247365) and the FP7 grant SACS (310651)

References [1] C. A. Strassert, L. De Cola et al. Angew. Chem. Int. Ed., 2011, 50, 946; M. Mauro, L. De Cola et al. Chem. Commun. 2014, 50, 7269; A. Aliprandi, M. Mauro, L. De Cola submitted [2] R. Corradini, L. De Cola et al Adv. Healthcare Mater. 2014, 3, 1812. [3] H. Lülf, A. Bertucci, D. Septiadi, R. Corradini, L. De Cola, Chem. Eu. J. 2014, 20, 10900. [4] L. De Cola, et al. submitted.

Functional systems can also be created using inert or active inorganic nanocontainers such as microporous and mesoporous silica based nanoparticles. In particular examples using the crystalline allumino silicates, zeolite L, and mesoporous organosilicates will be discussed since these materials can act as nanocontainers and due to their biocompatibility used for biomedical applications. The different functionalization of their surface will be discussed, in particular with the aim to show that the particles can be decorated with different functional groups including biocompatible molecules and are able to perfom drug and PNA delivery inside the cell [2,3]. The delivery can be probed by kinetic analyses after the nanoparticles internalization. In particular using confocal fluorescent microscopy it is possible to follow the release of each single component as well as the positioning of the nanocontainers in real time and space. Such achievement allows us to study the fate of the different units and their release time. However as many nanoparticles they are not biodegradable. Therefore at the end of the contribution very recent advances aiming to the creation of stimulus responsive particles that can break in vivo will be illustrated [4].

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Unravelling the surface ligand of quantum dots: upgrading the NMR toolbox to see the invisible

Fabien Delpech1, Yannick Coppel2, Wilfried-Solo Ojo1, Edwin Baquero1, Bruno Chaudret1, Bernhard Urbaszek1, Céline Nayral1

Université de Toulouse ; INSA, UPS, CNRS ; LPCNO (Laboratoire de Physique et Chimie des Nano-Objets), 135 avenue de Rangueil, F-31077 Toulouse, France. 2 Laboratoire de Chimie de Coordination, UPR-CNRS 8241, 205 route de Narbonne, 31077 Toulouse Cedex, France.

Over the last decade, semiconductor nanocrystals NCs- (also tagged quantum dots -QDs) have emerged as an important class of materials for applications ranging from electronics to biomedicine [1]. Significant achievements have been made possible thanks to the development of procedures leading to nano-objects of controlledshape, -structure, -composition (homogeneous, graded, core-shell), and surface chemistry (capping ligands) [1]. This latter feature is of key importance for the synthesis of NCs as well as for the optical and the transport properties of individual QDs or ordered-assemblies of QDs. These advances have been also provided by an increased knowledge in the understanding at the molecular scale of the interactions, the bonding modes, the dynamics and the reactivity of the ligands (whether organic or inorganic). However, the monitoring of the surface chemistry requires the development of analytical tools able to probe the composition of NC surfaces. Among the various used methods (that include infrared and X-ray photoelectron spectroscopies), solution nuclear magnetic resonance (NMR) stands out due the possibility (i) to distinguish between free and bound species (ii) to identify and quantify them, and (iii) to monitor the ligand dynamics [2]. Nevertheless, the in situ observation of moieties close to the surface as well as short ligands (OCH3, OH…) are precluded because of resonance broadening due to a distribution of chemical shift and of a manifold of capping ligand-NC bonding environment. This limitation is a major drawback since, for instance hydroxide ligand, which has been suspected but never evidenced, could be at the origin of the deterioration of the optical and electrical properties of PbSe QDs-based films [3]. We will here present a new NMR-based approach (named “Surface”) allowing for the first time the direct observation of ligand moieties and short ligands that are close to the NCs surface. This

TNT2015 toulouse (france)

fabien.delpech@insa-toulouse.fr

technique is based on magic angle spinning (MAS) NMR experiment and allows the characterization of ligands which are typically invisible using others classical spectroscopic means. This will be exemplified with Cd3P2 QDs coated with hexadecylamine (CH3(CH2)15NH2), acetate (CH3CO2) and hydroxyle (HO) ligands (Figure) [4].

References [1] M. V. Kovalenko, L. Manna, A. Cabot, Z. Hens, D. V. Talapin et al., ACS Nano 9 (2015) 1012. [2] A. Cros-Gagneux, F. Delpech, C. Nayral, A. Cornejo, et al. J. Am. Chem. Soc. 132 (2010), 18147. [3] J. M. Luther, M. Law, Q. Song, C. L. Perkin, M. C. Beard et al., ACS Nano 2 (2008) 271. [4] W.-S. Ojo, S. Xu, F. Delpech, C. Nayral, B. Chaudret, Angew. Chem. Int. Ed. 51 (2012) 738.

Figures

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AFM current-force spectroscopy of colloidal nanoparticle arrays 1

Institut d'Electronique, MicroĂŠlectronique et de Nanotechnologie, CNRS UMR 8520, France 2 Laboratoire de Physique & Chimie des Nano-Objets (UMR 5215, IRSAMC), INSA Toulouse, France

Conducting AFM current-force spectroscopy is performed on assemblies of colloidal nanoparticles coated by thiol and phosphine based ligands [1]. Complementary to macroscopic measurements, AFM allows addressing a few junctions and hence working at larger bias such that thermal activation due to possible Coulomb blockade effects [2] is negligible and a sequence of different tunneling regimes can be traversed. Decomposing the assembly into a resistor network (fig.1) furthermore gives access to the characteristics of the individual interparticle junction. Force dependent transition voltage spectroscopy is performed to study the effect of compression on the barrier height or band offset depending on whether tunneling through coherent levels [3] or vacuum barrier tunneling [4] is considered. In addition to the gain of fundamental knowledge about the applicable transport mechanism, different types of nanoparticles and ligands are compared with respect to their suitability for resistive strain gauges used in touch sensible panels on flexible substrates. The experimental work is completed by molecular dynamics simulation (fig.2).

H. Diesinger1, M. Biaye1, G. Copie1, C. Krzeminski1, F: Cleri1, N. Decorde2, J. Grisolia2, N.M. Sangeetha2, B. Viallet2, M. Gauvin2, L. Ressier, T. Melin1 h einrich.diesinger@isen.iemn.univ-lille1.fr

Figures

Figure 1. Realistic arrangement of nanoparticlaes into a hcp lattice; lateral current spread with increasing depth; junctions labeledYâ&#x20AC;&#x2122; are considered compressible

References [1] H. Moreira, J. Grisolia, N.M. Sangeetha, N. Decorde, C. Farcau, B. Viallet, K. Chen, G. Viau, and L. Ressier, Nanotechnology, 24(9)(2013), 095701 [2] K. H. Mueller, J. Hermann, G. Wei, B. Raguse, G. Baxter, and T. Reda, Phys. Rev. B, 66 (2002) 075417 [3] E. H. Huisman, C. M. Guedon, B. J. van Wees, S. J. van der Molen, NANO LETTERS 9 (11) (2009), 3909 [4] J.M. Beebe, BongSoo Kim, J. W. Gadzuk, C. Daniel Frisbie, and James G. Kushmerick, PRL, 97 (2006) 026801

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Figure 2. Molecular NP/thiol/NPjunction.

Dynamics

Simulation

TNT2015 toulouse (france)

Air-stable monocrystalline nickel nanorods and Ni-CNT hybrids for aeronautical applications 1

Glenna L. Drisko1, PierFrancesco Fazzini2, AnneFrançoise Mingotaud3, Brigitte Caussat4, Emmanuel Flahaut5, Pierre Fau1, Myrtil Kahn1

Nanochemistry, Organisation and Sensors, Laboratoire de Chimie de Coordination, France Laboratoire de Physique et Chimie des Nano-objets, Institut National des Sciences Appliquées, France 3 Laboratoire des Interactions Moléculaires et de la Réactivité Chimique et Photochimique, glenna.drisko@lcc-toulouse.fr Université Paul Sabatier, France 4 Laboratoire de Génie Chimique de Toulouse, France 5 CIRIMAT-LCMIE, Université Paul Sabatier, France 2

Nickel-carbon fiber-reinforced composites are of interest for aerospace vessels to increase the electrical conductivity of the light weight material, thus diminishing the risk of damage from electromagnetic radiation, electrostatic discharge and lightning strikes. Nickel nanowires and hybrid nickel-carbon nanotube materials are suitable nanostructures to ensure high conductivity at low mass loading. Monocrystalline nickel structures have even better conduction properties than the polycrystalline equivalent due to possessing less particle-particle junctions [1]. We have developed a solution-based method that produces monocrystalline nickel nanowires via decomposition of metal-organic precursors in the presence of self-assembled surfactants. The resulting wires are approximately 20 nm wide by 1.5 μm in length. The nanowires have a morphology consisting of semi-flattened rods with pyramidal ends. Despite the changing dimensions between the nanorod body and its head, there was no disruption in the crystallographic orientation, as observed with HRTEM and diffraction patterns (see figure). The nickel nanostructures were exposed to air for several weeks, but no oxidation was detectable by magnetic measurement, i.e. the saturation magnetization corresponds to Ni0 and no bias is observed in the hysteresis loops. It seems that the long alkyl chain amine surfactant, in addition to being a structuration agent, remains at the surface of the Ni wires after washing and acts as a protective layer. The distribution in the magnetic field along the Ni nanowire was imaged using magnetic force microscopy. It shows that one Ni wire is a magnetic monodomain.

TNT2015 toulouse (france)

Routes to prepare hybrid nickel-CNT materials were explored using chemical vapor deposition in a fluidized bed, solution chemistry and dry preparation in a Fisher-Porter reactor. Different nickel compositions and material morphologies resulted, depending on the preparation technique. The nickel nanorods and hybrid materials were incorporated into carbon fiber-reinforced polymer composites. The electrical conductivity as a function of wt% loading was measured, showing promise for these materials in discharging electrostatic charges.

References [1] Perry, N. H.; Mason, T. O. Solid State Ionics 181 (2010) 276.

Figures

Figure 1. Anisotropic monocrystalline nickel nanorod

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Self-Assembled Hollow SnO2 Octahedra for sub-ppm Gas Detection Sensors 1

Laboratoire de Chimie de Coordination (LCC), CNRS, Toulouse, France Université Paul Sabatier, UT III, Toulouse, France 3 Laboratoire d’Analyse et d’Architecture des Systèmes (LAAS), CNRS, Toulouse, France

Justyna Jońca1, Andrey Ryzhikov1, Myrtil L. Kahn1, Katia Fajerwerg1,2, Audrey Chapelle3, Philippe Menini3, Pierre Fau1,2

Nanostructures of SnO2 including nanoparticles,[1] nanowires,[2] nanobelts,[3] and nanotubes [4] have been widely used in many fields, such as gas sensors, solar cells and lithium batteries. Recently, hierarchical and/or hollow SnO2 micro- and nanostructures have attracted much interest because of their widespread potential applications such as gas sensors.[5] We present here the formation of self-assembled tin oxohydroxide (Sn3O2(OH)2) supercrystals organized in a “Russiandoll” structures and obtained by an organometallic synthesis, with finely tuned water addition. These supercrystals have been characterized by transmission and high resolution transmission electron microscopy, field-emission scanning electron microscopy, X-ray powder diffraction, and Fourier transform infra-red spectroscopy. These super-octahedra have been used as gas sensitive layers deposited on silicon devices. After in-situ heating, Sn3O2(OH)2 easily oxidizes into SnO2 while retaining the initial morphology and porosity (fig.1). The response of the sensors to reducing and oxidizing gases has been measured at relative humidity (RH) of 50%. At 500°C and under very low CO concentrations (0.25 to 20 ppm), the sensors present an outstanding dynamic response (7% and 67% of resistance variation) (Fig. 2). A response of 196% is obtained under 1 ppm NO2 at an operating temperature of 300°C. These unprecedented detection performances are strongly relied to the hierarchical microstructure of SnO2 supercrystals. These sensitive layers open the way to the development of metal oxide devices dedicated to extremely low gas concentration determination.

pierre.fau@lcc-toulouse.fr

References [1] C. Nayral, E. Viala, P. Fau, F. Senocq, J.-C. Jumas, A. Maisonnat, B. Chaudret, Chemistry, Eur. J. 2000, 6, 4082. [2] M.-S. Park, G.-X. Wang, Y.-M. Kang, D. Wexler, S.X. Dou, H.-K. Liu, Angew. Chem. 2007, 46, 750. [3] E. R. Viana, J. C. Gonzalez, G. M. Ribeiro, A. G. de Oliveira, J. Phys. Chem. C 2013, 117 (15), 7844. [4] L. Shi, H. Lin, Langmuir 2011, 27, 3977 ; J. Ye, H. Zhang, R. Yang, X. Li, L. Qi, small 2010, 6, 296. [5] H. Wang, A. L. Rogach, Chem. Mater., 2014, 26, 123

Figures

Figure 1. hollow SnO2 self-assembled octahedra

Figure 2. sub-ppm detection capability for SnO2 octahedra sensitive layer

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TNT2015 toulouse (france)

Optical and thermophoretic forces on plasmonic particles

Jochen Feldmann

feldmann@lmu.de

Photonics and Optoelectronics Group (PhOG) Ludwig-Maximilians-UniversitĂ¤t (LMU) Munich, Germany

www.phog.physik.uni-muenchen.de I will present our results on utilizing optical, optothermal and thermophoretic effects for a series of nanophotonic applications such as printing, sensing and optically induced motion (15). Examples range from controlled laser printing with nanoscale precision via optically driven elevation of Janus particles to the direct optical monitoring of microfluidic flow generated by bacterial flagellar rotation.

Figures

References [1] A. Ohlinger et al., Phys. Rev. Lett. 108, 018101 (2012) [2] S. Kirchner et al., Appl. Phys. Lett. 104, 9 (2014) [3] R. Schreiber et al, Nature Nanotechnology 9, 74 (2014) [4] M. Li et al., Nano Lett. 15, 770 (2015) [5] S. Nedev et al., ACS Photonics 2, 491 (2015).

TNT2015 toulouse (france)

september 07-11, 2015

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Graphene and 2D Hybrid Systems

Xinliang Feng

Department of Chemistry and Food Chemistry & Center for Advancing Electronics Dresden (cfaed), Technische Universitaet Dresden, Germany

The future research and application of graphene and 2D materials urgently calls for the efficient chemical synthesis and processing. In this lecture, top-down solution exfoliation of high-quality graphenes is firstly presented which relies on smart processing of graphitic materials at the different thickness level under electrochemical control. This strategy offers the possible means to produce high quality graphene, on a large scale, at low cost, and in a reproducible manner. In order to open up the band gap of graphene, a lateral confinement must be introduced, therefore, a bottom-up synthetic route will be demonstrated which offers welldefined nanographenes and graphene nanoribbons with tailor-made properties at the molecular level. This synthetic strategy is based upon the cyclodehydrogenation (â&#x20AC;&#x153;graphitizationâ&#x20AC;?) of welldefined dendritic (3D) polyphenylene precursors with different topologies, either by solution- or surface-mediated synthesis. We will further discuss the rational assembly of graphene sheets offering the fabrication of carbon and related 2D nanohybrid materials with different complexities. Finally, we will present some prominent applications with using these graphene materials as well as their nanohybrids across the fields of organic electronics, transparent electrode, fuel cells, supercapacitors and micro-supercapacitors as well as batteries.

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september 07-11, 2015

TNT2015 toulouse (france)

Understanding the Atomic Structure of Li-based Cathode Materials for Lithium-Ion Batteries by Advanced Transmission Electron Microscopy

P.J. Ferreira

Materials Science and Engineering Program, The University of Texas at Austin, Austin, TX, USA

In order for Li-ion batteries to mature to a level useful for integration into the current or future energy infrastructure, basic problems such as cyclability, cost and rate capability must be overcome. The spinel cathode materials of the type LiNixMn2-xO4 (LNM) (0<x≤½) have the advantage of being both cost-effective and high-rate capable materials, but they are plagued with cyclability problems. In the LNM system the main contributor to cycling degradation is the high operating voltage which leads to solid-electrolyte interphase (SEI) formation. To understand the passivation mechanism, it is crucial to determine the surface’s atomic structure as it defines how reactive the cathode will be with the electrolyte during oxidation and reduction cycles. Hence, it is critical to understand the different phases that form in this system.

TNT2015 toulouse (france)

In this regard, aberration-corrected transmission electron microscopy was used to identify the surface and bulk structures in the LNM system. The analysis confirms the spinel structure and shows good agreement with computer simulations in the bulk. Near the surface however, other phases are observed. These include a rock-salt structure which is expected from x-ray diffraction results and a new phase, defined here as “ring-type structure”, because of the characteristic rings that are formed within the first few atomic surface layers. All three phases are observed near the surface, however only the spinel is found within the bulk of the particles. This work enables us to develop a wellsuited cathode material for future energy storage that will potentially spur the evolution of the future sustainable energy landscape.

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Towards a Gold Nanoparticle-based Vaccine Directed against the Tumor Associated Mucin-1 Glycoprotein

Roberto Fiammengo1, Hui Cai2, Federica Degliangeli1, Björn Palitzsch3,‖ Bastian Gerlitzki4, Edgar Schmitt4 and Ulrika Westerlind2

Center for Biomolecular Nanotechnologies@UniLe – IIT, Lecce, Italy Gesellschaft zur Förderung der Analytischen Wissenschaften e.V. ISAS - Leibniz Institute for Analytical Sciences, Germany 3 Institute of Organic Chemistry, Johannes Gutenberg University of Mainz, Germany 4 University Medical Center, Institute of Immunology, Johannes Gutenberg University of Mainz, Germany 2

Mucin-1 (MUC1) has been identified as a top-priority cancer antigen for the development of therapeutic anticancer vaccines [1]. An effective strategy to enhance the immunogenicity of synthetic MUC1derived glycopeptides and thus to obtain promising vaccine candidates is to couple these glycopeptides to a carrier protein [2], to polymers [3] or selfassembling constructs [4] resulting in multivalent antigen presentation. We have developed PEGylated gold nanoparticles (AuNPs) which can be easily functionalized with a controllable number of peptides [5] and are expected to be ideally suited for the development of anticancer vaccines in view of their biocompatibility, simplicity of assembly and colloidal stability. In this contribution we describe the preparation and characterization of glycopeptide-functionalized AuNPs and we show that they induce specific antibodies directed against the tumor-associated form of MUC1. In particular, we immobilized chimeric peptides, consisting of a glycopeptide sequence derived from MUC1 and the T-cell epitope P30 sequence, on PEGylated AuNPs. Analysis of the antisera of immunized mice indicates a significant MHC-II mediated immune response. Furthermore, the antisera recognize their target antigen on human MCF-7 breast cancer cells. We also show that MUC1-

roberto.fiammengo@iit.it

P30 chimeric peptides, not coupled to AuNPs, are less effective in stimulating antibody production underlying the importance of their presentation on AuNPs. These results indicate that PEGylated AuNPs functionalized with MUC1-derived glycopeptides are very promising conjugates for the development of anticancer vaccines.

References [1] Cheever MA, Allison JP, Ferris AS, Finn OJ, Hastings BM, Hecht TT, Mellman I, Prindiville SA, Viner JL, Weiner LM, Matrisian LM, Clin Cancer Res, 17 (2009):5323-37. [2] Gaidzik N, Kaiser A, Kowalczyk D, Westerlind U, Gerlitzki B, Sinn HP, Schmitt E, Kunz H, Angew Chem Int Ed, 42 (2011):9977-81. [3] Nuhn L, Hartmann S, Palitzsch B, Gerlitzki B, Schmitt E, Zentel R, Kunz H, Angew Chem Int Ed, 40 (2013):10652-6. [4] Huang Z-H, Shi L, Ma J-W, Sun Z-Y, Cai H, Chen Y-X, Zhao Y-F, Li Y-M, J Am Chem Soc, 21 (2012):8730-3. [5] Maus L, Dick O, Bading H, Spatz JP, Fiammengo R, ACS Nano, 11 (2010):6617-28.

Figures

Figure 1. Left: Schematic structure of the immunized three-component AuNP-P30-MUC1 vaccine candidate with 3 Tn glycosylation sites. Right: Total antibody titers after the third bleed determined by ELISA.

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TNT2015 toulouse (france)

High selectivity of pure semiconductor single walled carbon nanotubes for optoelectronic telecom applications 1

Department of Physics and LENS, University of Florence,Italy CEA Saclay, IRAMIS, NIMBE (UMR 3685), LICSEN, France

F. Sarti1, F. Biccari1, F. Fioravanti1, U. Torrini1, A. Vinattieri1, M. Gurioli1 ,A. Keita2, M. Balestrieri2, V. Derycke2, A. Filoramo2

We report a detailed protocol for selecting very pure large diameter semiconductor single walled carbon nanotubes (s-SWNTs) with fundamental transition centered at 1550 nm. We use poly[(9,9dihexylfluorenyl-2,7-diyl)-co-(9,10-anthracene)] (PFH-A), producing samples with narrow and bright excitonic emission in toluene solution. Optimized sonication and centrifugation protocols are used to eliminate any trace of metallic carbon nanotubes. We characterize the samples both with optical and electrical measurements. Bright and sharp exciton emissions are eventually found even from dried sSWNTs after deposition with drop cast method on quartz. We exploit the Resonant Raman spectroscopy to increase the detectability of residual presence of metallic single walled carbon nanotubes (m-SWNTs). Demonstration of the complete absence of m-SWNTs is obtained also by electrical measurements on carbon nanotube transistors with different channel lengths. Our findings pave the way to exploit s-SWNTs for optoelectronic devices in the telecom wavelengths.

This work was funded by the European Union through the FP7 Project CARTOON (Contract FP7 618025).

TNT2015 toulouse (france)

september 07-11, 2015

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Comparison of the environmental impact of carbon nanoparticles (carbon nanotubes, nanodiamonds, few-layer graphene) 1

CIRIMAT, UMR 5085, Université Paul Sabatier, Toulouse, France ECOLAB, UMR 5245, Toulouse, France 3 CEA, Diamond Sensors Laboratory, Gif sur Yvette, France 4 UCLM, Spain

Emmanuel Flahaut1, Florence Mouchet2, Antoine Mottier2, Cyril Sarrieu1, Stéphanie Cadarsi2, Laura Lagier2, Jean-Charles Arnault3, Ester Vazquez4, Eric Pinelli2 and L. Gauthier2

Carbon nanoparticles have exceptional properties and already used in numerous industrial applications. For this reason, we expect that they may ultimately get into the environment along their life cycle (from production to end of life of goods including them), and especially in the water. This work deals with the ecotoxicological assessment of different carbon nanoparticles (CNPs) in the aquatic compartment by comparing the effects of different nanocarbons: Carbon Nanotubes (CNTs: doublewalled and multiwalled), few-layer graphene (FLG), and nanodiamonds (ND), using the ISO 21427-1 biotoxicity assay on Xenopus laevis larvae. Three different endpoints were investigated after 12 days of exposure: (i) acute toxicity (mortality), (ii) chronic toxicity (growth inhibition) and (ii) genetic toxicity (micronucleus assay). Beside toxicity bioassays, a complete characterization of nanocarbons was undertaken. Neither mortality nor genotoxicity was observed regardless of these types of nanocarbons. Only growth inhibition was observed and depended on the nature of the nanocarbon. Growth inhibition expressed using three different metrics (mg.L-1; number of particles.mL-1 and surface area in m²) showed that the toxicity of the investigated nanocarbons seems to depend mainly on the total surface area of the nanoparticles. Furthermore, we hypothesize that toxicity observed in larvae exposed to high concentrations of nanocarbons would be limited to physical effects (gill clogging and/or abrasive effects and or nutrients deprivation).

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TNT2015 toulouse (france)

Strong coupling between organic molecules and surface plasmons

Francisco J. García-Vidal Fj.garcia@uam.es

Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain

In this talk I will present an overview of the theoretical work developed in our group to understand from a fundamental point of view the phenomenon of strong coupling between organic molecules and surface plasmons. First, I will present the case of a single quantum emitter in close proximity to a 2D metal surface [1] and study under which conditions strong coupling between the exciton mode in the emitter and the propagating surface plasmons supported by a 2D metal surface could emerge. Next I will revisit the case of an ensemble of molecules interacting with a 2D metal surface [2], the system in which strong coupling was firstly observed experimentally.

References [1] A. Gonzalez-Tudela, P.A. Huidobro, L. MartinMoreno, C. Tejedor and F. J. García-Vidal, Phys. Rev. B (RC) 89, 041402 (2014). [2] A. Gonzalez-Tudela, P.A. Huidobro, L. MartinMoreno, C. Tejedor and F. J. García-Vidal, Phys. Rev. Lett. 110, 126801 (2013). [3] A. Delga, J. Feist, J. Bravo-Abad and F. J. García-Vidal, Phys. Rev. Lett. 112, 253601 (2014). [4] J. Feist and F.J. Garcia-Vidal, Phys. Rev. Lett. 114, 196402 (2015).

I will also present the case of organic molecules interacting with the localized surface plasmons supported by a metal nanoparticle [3] and the interplay between quenching and strong coupling in this type of structures. Finally, I will show how exciton conductance in organic materials can be enhanced by several orders of magnitude when the molecules are strongly coupled to a plasmonic mode [4]. I will demonstrate how the formation of a collective polaritonic mode allows excitons to bypass the disordered array of molecules and jump directly from one end of the structure to the other. This finding could have important implications in the fields of exciton transistors, heat transport, photosynthesis, and biological systems in which exciton transport plays a key role.

TNT2015 toulouse (france)

september 07-11, 2015

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Hybrid Spintronic-MEMS Devices

J. Gaspar, H. Fonseca, M. Costa, E. Paz, S. Cardoso, R. Ferreira, and P. P. Freitas

International Iberian Nanotechnology Laboratory (INL), Braga, Portugal

joao.gaspar@inl.int

This work reports on our latest developments about the integration of spintronic sensors with micro- and nanoelectromechanical systems (MEMS and NEMS) devices, including (i) state-of-art magnetic tunnel junctions (MTJ) embedded in flexible probes for nonplanar geometry applications, (ii) magnetic field modulators based on large displacement micromechanical actuators, (iii) micromachined silicon tips with spin valves for brain activity recording and monitoring, and (iv) atomic force microscopy (AFM) cantilevers with sub-µm magnetic sensors at their tips for scanning magnetoresistancebased applications. To illustrate some of those results here, we managed to integrate for the first time MTJ sensing devices with magnetoresistance responses above 150% on flexible substrates, as opposed to previous attempts in which figures below 53% have been obtained [1]-[3]. These are able to bend and conform to non-planar geometries, non-conformal and hard-to-reach regions of space for magnetic sensors processed in conventional rigid substrates, paving the way for new spintronic applications. Their fabrication process is based on polyimide (PI) materials due to their flexibility, thermal stability, chemical resistance, high mechanical modulus, and biocompatibility. Magnetoresistive performance is characterized in terms of controlled mechanical load conditions. The fabrication summarized in Fig. 1 begins with the definition of the MTJ sensors on a PI layer atop SiO2/Si. The MTJ stack is patterned by photolithography/ion milling and annealed to obtain magnetic sensors as detailed elsewhere for rigid substrates [4]. The subsequent step is another PI coating acting as encapsulation. The PI layers are

patterned to define the shape of the flexible device and probes are finally detached from the rigid substrate by means of HF vapor that selectively removes the underlying sacrificial layer. The overall flexible probe thickness is slightly larger than 20 µm. Layouts of devices fabricated using such technology are shown in Figs. (2) and (3), corresponding to long magnetic sensing stripes and neural insertion probes, respectively. The stripes consist of ca. 50mm-long, 4.5-mm-wide structures with MTJ arrays located at their centers, each MTJ connected in a 4wire configuration, and are used to analyze magnetoresistive performance as a function of mechanical loading. As for the neural insertion/magnetic recording probes, Fig. (3), they consist of ca. 30-mm-long devices with an opening of 90 µm at one end, compatible with surgery tools used for brain insertion. Devices comprising squareshaped impedance electrodes with 30 µm and MTJ sensors with pillars ranging from 4 to 20 µm have been processed, Figs. (4) and (5). Figure (6) shows the transfer curve of a sensor with area (pillar dimension), A, of 8x8 µm2 in a released, unloaded probe with resistance, Rmin, magnetoresistance ratio, MR, and sensitivity, dV/dH, of 145 , 171% and 250 µV/Oe, respectively.

References [1] [2] [3]

Melzer et al., Nano Lett., vol. 11, no. 6, p. 2522 (2011). Y. Chen et al., Advanced Materials, vol. 20, no. 17, p. 3224 (2008). C. Barraud et al., Appl. Phys. Lett., vol. 96, no. 7, p. 072502 (2010).

Figures

Figure 1. Fabrication schematics of flexible probes with magnetic sensors, (2)-(3) representative layouts, (4)-(5) fabricated devices and (6) output curves.

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TNT2015 toulouse (france)

Bio-Inspired Building Blocks for Organic Nanotechnology

Ehud Gazit ehudg@post.tau.ac.il

Department of Molecular Microbiology and Biotechnology, Department of Materials Science and Engineering, Tel Aviv University, Tel Aviv, Israel

Organic nanotechnology is clearly a new front in the field of molecular self-assembly of new structures and composite families at the nano-scale. Our works on the mechanism of aromatic peptide selfassembly, lead to the discovery that the diphenylalanine recognition motif self-assembles into peptide nanotubes with a remarkable persistence length. Other aromatic homodipeptides (including those with non-coded amino acids as DOPA) could self-assemble in nano-spheres, nanoplates, nano-fibrils and hydrogels with nano-scale order. The modification of peptide building blocks with the Fmoc protecting group allows the formation of hydrogels with nano-scale order. We demonstrated that the peptide nanostructures have unique chemical, physical and mechanical properties including ultra-rigidity as aramides, semi-conductive, piezoelectric and non-linear optic properties. We also demonstrated the ability to use these peptide nanostructures as casting mould for the fabrication of metallic nano-wires and coaxial nano-cables. The application of the nanostructures was demonstrated in various fields including electrochemical biosensors, tissue engineering, and molecular imaging. We had developed ways for depositing of the peptide nanostructures and their organization. We had use inkjet technology as well as vapour deposition methods to coat surface and from the peptide “nano-forests”. We recently demonstrated that even a single phenylalanine amino-acid can form well-ordered fibrilar assemblies of distinct electron diffraction pattern and toxic properties. The combination of DNA properties and peptide backbone in the form of Peptide Nucleic Acid (PNA) resulted in light emitting assemblies that exhibit both stacking and Watson-Crick base-pairing.

TNT2015 toulouse (france)

Selected References [1] Reches, M. and Gazit, E. (2003) Casting Metal Nanowires within Discrete Self-Assembled Peptide Nanotubes. Science 300, 625-627. [2] Reches, M. and Gazit, E. (2006) Controlled Patterning of Aligned Self-Assembled Peptide Nanotubes. Nature Nanotechnology 1, 195200. [3] Mahler, A., Reches, M., Rechter, M., Cohen, S., & Gazit, E. (2006). Rigid, Self-Assembled Hydrogel Composed of a Modified Aromatic Dipeptide. Adv. Mater. 18, 1365-1370. [4] Adler-Abramovich L., Aronov D., Beker P., Yevnin M., Stempler S., Buzhansky L., Rosenman G. and Gazit E. (2009) SelfAssembled Arrays of Peptide Nanotubes by Vapour Deposition. Nature Nanotechnology 4, 849-854. [5] Adler-Abramovich, L., Vaks, L., Carny, O., Trudler, D., Frenkel, D., & Gazit, E. (2012) Phenylalanine Assembly into Toxic Fibrils Suggests Amyloid Etiology in Phenylketonuria. Nature Chem. Biol. 8, 701-706. [6] Levin, A. Mason, T. O., Adler-Abramovich, L., Buell, A. K., Meisl, G., Galvagnion, C., Bram, Y., Dobson, C. M., Knowles, T. P. J., & Gazit, E. (2014) Ostwald’s Rule of Stages Governs Structural Transitions and Morphological Control of a Dipeptide Supramolecular Polymer. Nature Commun. 5:5219. [7] Berger, O., Adler-Abramovich, L., Levy-Sakin, M., Grunwald, A., Liebes-Peer, Y., Bachar, M., Buzhansky, L., Mossou, E., Forsyth, V. T., Schwartz, T., Ebenstein, Y., Frolow, F., Shimon, L. J.W., Patolsky, F. & Gazit E. (2015) Light Emitting Self-Assembled Peptide Nucleic Acids Exhibit Both Stacking and Watson-Crick BasePairing. Nature Nanotechnology 10, 353-360.

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Design of Copper-based Coatings for Bactericidal Applications 1

Laboratoire de Chimie de Coordination du CNRS, France Université de Toulouse, UPS, INPT, France 3 Laboratoire de Génie Chimique, INP-ENSIACET, France 4 Institut de Pharmacologie et de Biologique Structurale, France 2

Arnaud Glaria1, Aurélien Hameau1,2, Pierre Fau1,2, Christine Roques3, Julien Grimoud3, Anne-Marie Caminade1, Romain Laroche4, Fabienne Bardou4, Cédric-Olivier Turrin1 pierre.fau@lcc-toulouse.fr

The spreading of nosocomial infections (NIs) in a medical environment is a major issue that Health Organizations have to tackle worldwide. Three germs are responsible for more than 50% of all NIs: Escherischia coli (urinary tract infections), Staphylococcus aureus (respiratory infections, infection of surgery site) and Pseudomonas aeruginosa (respiratory infections, urinary tract infections). These germs have developed strong resistances towards antibiotherapies and NIs induce each year a dramatic over cost in all countries. In order to save patient lives and to reduce the burden of the induced costs, many prevention protocols have been developed. However, one other way to avoid the formation of bacteria colonies in a hospital environment is to design active surfaces able to impede the growth and/or to kill pathogenic cells. During the past decades, silver nanoparticles have been used in many commercial bioactive devices or coatings but their bactericidal property are also shared by copper materials. [1] Thus, bioactive thin films containing Cu NPs should be of great interest for surface treatments and anti-biofilm purposes with low copper loading in the 1% mass loading range. Moreover, the control of the stability of the coating as well as the possible release of metal ions have to be considered in order to design a smart bactericidal surface. [2] To fulfill these requirements we have developed a multi-step approach starting from the study of individual copper NPs towards their assembly onto a multilayer structure (Figure 1). First, we evaluated different types of organic molecules, exhibiting either weak (amines) or strong (phosphonic acids) affinity for the NPs’ surface and we highlighted the discrepancies between the ligands for the NPs’ functionalization. [3] We also focused on the role of complex macromolecules such as polymers,

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dendrons or dendrimers which have proved to strongly adhere to several surfaces and allowed to form a polymeric matrix embedding the NPs. [4] Finally, we were able to attach the copper particles to a silanized surface and to build up a complex structure by means of either a direct in situ synthesis or using a standard coating procedures. Now, the activity of the resulting materials is tested against different types of bacteria, such as P. aeruginosa, E. coli or S. aureus, and the first results will be compared to the ones obtained with conventional antibiotics.

References [1] a) F. Cheng; W. J. Betts, S.M. Kelly, J. Schaller, T. Heinze, Green Chemistry, 15 (2013) 989; (b) A. L. Casey, D. Adams, T. J. Karpanen, P. A. Lambert, B. D. Cookson, P. Nightingale, L. Miruszenko, R. Shillam, P. Christian, T. S. J. Elliott, J. Hosp. Infect. 74 (2010), 72e77; (b) K. C. Anyaogu, A. V. Fedorov, D. C. Neckers, Langmuir 24 (2008) 4340. [2] (a) G. Applerot, J. Lellouche, A. Lipovsky, Y. Nitzan, R. Lubart, A. Gedanken, E. Banin Small 8 (2012) 3326; (b) C. Gunawan, W. Y. Teoh, C. P. Marquis, R. Amal, ACS Nano 5 (2011) 7214. [3] (a) A. Glaria, J. Cure, K. Piettre, Y. Coppel, C. O. Turrin, B. Chaudret, P. Fau, Chem. Eur. J. 21 (2015) 1169. [4] (a) W. B. Zhao, J. Park, A.-M. Caminade, S.-J. Jeong, Y. H. Jang, S. O. Kim, J.-P. Majoral, J. Cho, D. H. Kim, J. Mater. Chem. 19 (2009) 2006; (b)] A. Hameau, V. Collière, J. Grimoud, P. Fau, C. Roques, A.M. Caminade, C.O. Turrin, RSC Adv. 3 (2013) 19015.

TNT2015 toulouse (france)

Graphene monolayer produced on Pt reusable substrates for transparent conductive electrodes applications

luana.golanski@cea.fr

CEA, MINATEC Campus, F-38054 Grenoble, France

Large-scale growth of graphene materials by CVD is commonly realized on Cu substrates for transparent conductive electrodes applications [1]. However, this Cu-based technology induces chamber pollution difficult to clean and not compatible with further microelectronic processing. In this work, we report on a graphene production process using CVD technique on Pt thin film covered substrate. Considering the cost ratio between platinum and copper we just need to reuse the substrate 20 times to be cost effective as compared with copper foil use. As compared with growth on Cu films the graphene grown on Pt films exhibit only few ripples thanks to the lower substrate temperature and smaller coefficient of expansion of Pt as compared with Cu. We developed a growth process allowing high quality graphene single layer using an microelectronic industrial tool able to deposit graphene on 200mm substrates. Growth was achieved by catalytic decomposition of CH4 at a very low CH4/H2 flow rate ratio in order to lower the nucleation density of graphene on Pt and favor large graphene grains on Pt. Graphene production with nucleation control is obtained on Pt thin film substrates at 800°C compared to 1000°C for Cu. In these conditions, grains with typically tenth of µm size are obtained. Each grain is formed with high quality single crystal without any obvious atomic defect as seen by HRTEM (Figure 1a). In order to better assess the graphene quality, Raman spectra were acquired and Raman mapping performed (Figure 1b). The intensity ratio (IG / I2D) around 0.3 testify that the deposited graphene is made of a single layer at least on the area tested (25x25µm) [4]. For further integration of graphene into applicative devices, a clean transfer from metal substrates

L.Golanski, D.Rouchon, H. Okuno, J.Dijon, E.Quesnel, P.Fugier

preserving the integrity of graphene sheet, remains a challenge that needs to be overcome [1]. We tested two non-destructive transfer techniques which should allow to re-use the Pt substrates, such as an electro-chemical method [2] or a dry transfer approach [3]. Graphene sheets transferred by electro-chemistry showed a good quality: density of defects such as cracks, holes are minimized. Moreover, after the electro-chemical transfer, TEM analysis confirmed only quite few metal contamination less than with graphene obtained by conventional Cu dissolution transfer method. As dry transfer, the delamination of a graphene monolayer by the stress accumulated in Ni films has been also tested to transfer graphene grown on Pt substrate. The sheet resistance of a monolayer of graphene transferred on glass by an electrochemical process is around RS = 1300 Ω/square (four point method). By improving this route we will be able to produce high quality contaminant free graphene grade material.

References [1] Ren, W., Cheng, H-M. Nature Nanotechnology, 9 (2014) 726-730 [2] Kim, J., Park H., Hannon, J.B., Bedell, S.W, Fogel, K., Devendra, K.S, Dimitrakopoulos, C. Science 342 (2013), 833-836 [3] Gao, L., Ren, W., Xu, H., Jin, L., Wang, Z., Ma, T., Ma, L-P, Zhang, Z., Fu, Q., Peng, L-M, Bao, X., Cheng, H-M. Nature Communications, (2012), 3-7 [4] Ferrari, A. C. (2007) Raman spectroscopy of graphene and graphite: Disorder, electron– phonon coupling, doping and nonadiabatic effects, Solid State Commun, Vol 143, 47-57

Figures

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Figure 1. : a) Low-pass filter atomic resolution TEM images of graphene grown on Pt b) Raman mapping of a transferred graphene /SiO2 by electrochemistry method on 25x25µm.

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Chemical Characterization of MoS2 using Theoretical AFM

César González1,2, Yannick J. Dappe2 and Blanca Biel1

Departamento de Electrónica y Computadores, Universidad de Granada, Spain SPEC (DSM/IRAMIS/SPEC, CNRS UMR 3680, CEA Saclay, France

Since graphene was discovered some years ago [1], the interest for two dimensional (2D) materials has grown exponentially. The so-called transition-metal dichalcogenide (MX2) have recently attracted a great attention due to their promising properties. One of the most studied MX2 compounds is the MoS2 due to its semiconducting character and its possible nanoelectronic, optoelectronic and spintronic applications [2]. This material has been studied with different techniques but a complete atomic force microscopy analysis (AFM) cannot be found in the literature. In this work, we have performed density functional theory (DFT) simulations based in the VASP code [3] in order to present a detailed AFM analysis of a perfect MoS2 monolayer (together with its most characteristic defects) using different tips: a low/high interacting Si/Cu tip and the recently developed stable C-based tip [4]. Our results allow us to identify the different defect presented in a MoS2 monolayer, confirming the higher chemical interaction obtained when any atomic vacancy is examined. As expected, the metallic tip presents the highest interaction. Finally, the graphitic tip shows the lowest reactivity and a great stability, even when the van der Waals (vdW) forces are included in the calculation. This result confirms the graphitic tip as adequate for AFM measurements, especially with highly reactive systems where the atomic transfer is undesirable and it can be expected with other tips.

gonzalezcesar@ugr.es

References [1] K. S. Novoselov et al. Science 306, (2004) 666669 [2] B. Radisavljevic et al. Nat. Nanotechnol. 6 (2011) 147; J. Yoon et al. Small 9 (2013) 3295; Q. H. Wang et al. Nat. Nanotechnol. 7 (2012) 699 [3] G. Kresse and J. Hafner, Phys. Rev. B 47 (1993) R558; G. Kresse and J. J. Furthmuller, Phys. Rev. B 54 (1996) 11169; G. Kresse and D. Joubert,Phys Rev B 59 (1999) 1758 [4] Y. J. Dappe, C. González and J. C. Cuevas, Nanoscale 6 (2014) 6953

CG acknowledges funding from Andalusian Agency of Knowledge and the 7th Framework Programme via the Marie Curie Action, “Co-funding of Regional, National and International Programmes” through the Andalucia Talent Hub grant.

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Figures

Figure 1. : Schematic representation of a Cu tip over a S atom in the MoS2 monolayer for long distance and in the contact regime together with the force curves obtained over the S and Mo atoms and their corresponding vacancies. In the inset, the same result obtained over a Mo atom using a low interacting Si-tip.

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Quantum optics with surface plasmons 1

L. C Fabry, Institut d'Optique, CNRS, Université Paris Sud, 2 av Fresnel, 91127 Palaiseau Cedex, France 2 LPEM, ESPCI-Paris Tech, PSL Research University, CNRS, Sorbonne Université, UPMC paris VI, 10 rue Vauquelin, 75005 Paris, France 3 Laboratoire Photonique, Numérique et Nanosciences, Institut d'Optique d'Aquitaine, Université de Bordeaux, Talence, France 4 Institut de Science et d'Ingénierie Supramoléculaire, Université de Strasbourg, CNRS, Strasbourg, France

Jean-Jacques Greffet1, MarieChristine Dheur1, B. Habert1, Eloise Devaux3, T. W Ebbesen3, A. Baron1, JP Hugonin1, P. Lalanne3, G. Messin1, F. Marquier1, B. Ji4, E. Giovanelli4, P. Spinicelli4, M. Nasolawski4, X. Xu4, N. Lequeux4, B. Dubertret4 jean-jacques.greffet@institutoptique.fr

This presentation reviews recent works on surface plasmons in the quantum regime. In the first part of the talk, I will present a core-shell gold plasmonic resonator (hereafter called golden quantum dot) used to tailor the spontaneous emission of a single quantum dot. In the second part of the talk, I will present a recent experiment performed with surface plasmons propagating along a metal/air interface. Here, we aim at reproducing with plasmons a seminal experiment of quantum optics demonstrating the waveparticle duality.

and detect one of them to herald the arrival of the second one. This heralded photon is converted into a plasmon which is sent onto a beam splitter. We then study the correlation of the outputs of the beam splitter and observe a very strong anti bunching. This single plasmon is subsequently sent into a Mach-Zehnder interferometer allowing the observation of interferences in the single plasmon regime.

It has been known for decades now that the spontanoeus emission rate is not an intrinsic property but depends on the environment. It is possible to use plasmonic strutures to tailor the environment. Here, we use a golden quantum dot which consists in a CdS/CdSe quantum dot covered with silica and a 20 nm gold shell. The system has been synthesized in the group of the ESPCI [1]. By properly designing the system, it has been possible to observe a significant spontaneous emission rate acceleration on the order of 10. This is due to the modification of the local density of states in the plasmonic cavity. A remarkable property of these golden quantum dots is that they do not blink. Furthermore, they are very robust against photobleaching even when they are illuminated in the saturation regime.

[1] Non-blinking quantum dots with a plasmonic nanoshell resonator, B. Ji, E. Giovanelli, B. Habert, P. Spinicelli, M. Nasolawski, X. Xu, N. Lequeux, JP Hugonin, F. Marquier, JJ Greffet, B. Dubertret, Nature Nanotechnology, 10 (2015) 170. [2] Wave-particle duality with nonclassical surface plasmons, MC Dheur, E. Devaux, T W Ebbesen, A. Baron, JP Hugonin, P. Lalanne, JJ Greffet, G. Messin, F. Marquier, in preparation.

References

The second part of the talk reports a recent quantum optics experiment with surface plasmons. We have designed and fabricated a surface plasmon platform that includes couplers to convert photons into plasmons and surface plasmon beam splitters. We generate a pair of identical photons

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Non-exponential resistive switching in Ag2S memristors: a key to nanometer-scale non-volatile memory devices

Agnes Gubicza, Miklós Csontos, András Halbritter, György Mihály

gubicza@dept.phy.bme.hu Department of Physics, Budapest University of Technology and Economics, Hungary

Future technological developments in non-volatile resistance switching random access memory (ReRAM) applications [1] exceeding the limitations of present-day flash devices are expected to comply with the basic requirements of a small size for a high data storage density as well as fast read and write operations performed at reasonably low voltages and easily detectable current levels. Moreover, it is also a key issue that such passive circuit elements exhibit a strongly non-linear response function, so that the device is stable against low-level read-out signals and, at the same time, responds quickly to write operations carried out at higher biases. Tunable, nanometer scale junctions formed between metallic electrodes by reversible solid state electrochemical reactions represent extremely promising candidates to satisfy the above criteria [2]. The resistive state of such a memory element, called memristor [3] is altered by biasing the device above its writing threshold (Vth). Readout is performed at lower signal levels which preserve the stored information. We studied the dynamics of the resistive switchings in Ag–Ag2S–PtIr nanojunctions [4]. We showed that the resistance change simultaneously exhibits multiple time scales ranging from a nanosecond to

seconds upon a switching voltage pulse. The resulting non-exponential transition between the OFF and ON states as well as the achievable, technologically convenient ROFF/RON = 2–10 ratios are largely affected by the amplitude and frequency of the biasing signals. This fundamental, inherent property of the Ag2S ionic conductor provides the unique opportunity for combination of GHz write/erase operations [5] performed at bias levels of a few Volts, non-volatile read-out with slower signals of a few 10 mV and robust information storage at zero bias in a two-terminal, nanometer scale analog memory device.

References [1] [2] [3] [4] [5]

J.J. Yang et al., Nature Nanotechnology, 8, (2013) 13. R. Waser et al., Adv. Mater., 21, (2009) 2632. L. Chua, IEEE Trans. Circuit Theory, 18, (1971) 507. A. Gubicza, M. Csontos, A. Halbritter, G. Mihály, Nanoscale, 7 (2015) 4394. A. Geresdi, M. Csontos, A. Gubicza, A. Halbritter, G. Mihály, Nanoscale, 6 (2014) 2613.Wu, J.; Duan, W. H.; Gu, B. L.; Yu, J. Z.; Kawazoe, Y. Appl. Phys. Lett., 77 (2000) 2554–2556.

Figure 1. Resistance ratio ROFF/RON as a function of the driving frequency and amplitude as deduced from the hysteretic I-V traces recorded in PtIr-Ag2S-Ag nanojunctions established in an STM setup.

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Effective Magnetization Damping in Inhomogeneous Spin Textures: Vortices and Skyrmions

Konstantin Gusliyenko1,2, Oksana Sukhostavets1 and Julian Gonzalez1

Dpto. Física de Materiales, Universidad del País Vasco, UPV/EHU, San Sebastián, Spain IKERBASQUE, The Basque Foundation for Science, 48013 Bilbao, Spain

Recently, new inhomogeneous magnetization objects - magnetic skyrmions - vortex-like curling spin textures with a quantized topological number have been observed in chiral magnets possessing Dzyaloshinskii-Moriya exchange interaction as well as in traditional ferromagnetic materials (bubbleskyrmions). Skyrmions attracted considerable attention of researchers assuming potential applications in spintronic devices because their motion can be controlled with ultralow current density [1]. To achieve efficient manipulation of nanosized spin textures and realize skyrmion-based new brand spintronic devices, it is essential to understand skyrmion motions in confined geometries, for instance, in magnetic nanodots and stripes. The motion of skyrmions in such patterned nanostructures is essentially influenced by their energy dissipation – magnetization damping. In this work we investigate in detail the magnetization damping of dynamical vortex and bubble-skyrmion spin textures in circular ferromagnetic dots. We use an extension of the Landau-Lifshitz-Gilbert equation of magnetization motion considering an additional damping contribution coming from the conduction electrons in the case of inhomogeneous magnetization distributions (such as vortices and skyrmions) in ferromagnetic metals. The additional magnetization damping is calculated using the s-d exchange model. The effect of conduction electrons on the magnetization dynamics is accounted assuming a slowly varying spin texture within an adiabatic approximation by using a coordinate transformation to the local quantization axis parallel to the magnetization vector. The additional damping appears due to spin currents generated by emergent electric fields, which are determined by the spatial and time derivatives of the moving magnetization. The moving magnetic vortex in a circular permalloy nanodot and bubble-skyrmion in

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kostyantyn.gusliyenko@ehu.es

a circular dot with a moderate perpendicular magnetic anisotropy [2] are considered as examples. The value of the damping and its dependence on the geometrical sizes of the dots is obtained [3]. It is found that the additional damping can reach 20% of magnitude of the phenomenological Gilbert damping for the vortex case and is comparable with the Gilbert damping for moving bubble-skyrmions. Therefore, this contribution to the magnetization damping should be taken into account for inhomogeneous spin texture dynamics in patterned films made of ferromagnetic metals.

References [1] A. Fert, V. Cros, and J. Sampaio, Nat. Nanotechn. 8 (2013) 152. [2] K.Y. Guslienko, Magn. Lett., IEEE 6 (2015) 4000104. [3] O.V. Sukhostavets, J. Gonzalez, and K.Y. Guslienko, Low Temp. Phys., submitted (2015).

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AFM Mechanical Characterization And Four-Probe/SEM Measurement Of Hybrid Metallic/Inorganic Nanosprings

S. Habtoun1,2, M. Berthe3, S. Houmadi1, B. Reig1, D. Dedovet4,5, E. Pouget4,5, R.Oda4,6, M-H. Delville4,6, C. Bergaud1

CNRS, LAAS, 7 avenue du Colonel Roche, F-31400 Toulouse, France Univ. de Toulouse, INSA, LAAS, F-31400 Toulouse, France 3 IEMN, Avenue Poincaré - CS 60069 – 59652 Villeneuve d’Ascq CEDEX, France 4 IECB, Rue Robert Escarpit, 33607 Pessac, France 5 CBMN, Allée Geoffroy Saint Hilaire, Bât B14, 33600 Pessac, France 6 ICMCB, 87 Avenue du Dr Albert Schweitzer, 33600 Pessac, France 2

Helical nanostructures [1,2] have attracted tremendous attention in the last decade. Their unique periodic geometry, chirality and high surface/volume ratio combine striking features from both 1D and 3D nano-objects. This paper proposes a novel method to clamp and locally metallize in one step suspended inorganic nanosprings. Electron-beam and Ion-beam induced deposition (EBID/IBID) of platinum were carried out on silica nanosprings fabricated by sol-gel replication of organic self-assemblies[3]. We then performed 3point bending tests with Atomic Force Microscopy[4] and 4-probe measurements inside a SEM/STM[5] along the length of the nanostructures to characterize both mechanical and electrical properties of our nanostructures. The results obtained show that the resulting nanoobjects exhibit stiffnesses ranging from 0.5 to 10N/m, and electrical resistance from 1 to 100 kΩ while keeping an ohmic behavior. COMSOL simulations were carried out and confirmed these results. This shows that our method can successfully be used to tune the properties of these hybrid nanosprings, which can thus be advantageously employed for fabricating highly sensitive NEMS with piezoresistive detection.

habtoun@laas.fr

Figures

Figure 1. SEM image of a suspended nanospring after clamping and Pt IBID– inset: AFM image of a nanospring on a flat substrate.

References [1] [2] [3] [4]

D. N. McIlroy et al, APL, 79 (2001) 1540–1542 Y. Wang et al, Chem. Soc. Rev., 42 (2013) 2930–2962 T. Delclos, et al, Nano Letters 8 (2008), 1929-1935 S. Houmadi et al, Appl. Phys. Lett. 102 (2013), 151904/151901-151904/151905 [5] M. Berthe et al, Atomic Scale Interconnection Machines (2012), pp107-118

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Figure 2. Setup inside the Nanoprobe. Inset: 4-probe measurement along one nanospring.

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Figure 3. Resistances obtained with EBID (left) and IBID (right) metallized nanosprings. Thick layers (low L/S) show a linear resistance which agrees with a tubular modelling. Thin layers keep a helical structure

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Structures and Characteristics of noble metal nanoparticles in nanocomposites & gels via exfoliated clay mediated in-situ reduction

Kazutoshi Haraguchi1 and Dhamesh Varade2

haraguchi.kazutoshi@nihon-u.ac.jp

Dep. of Applied Molecular Chemistry, College of Industrial Technology, Nihon University, Chiba, 275-8575 Japan 2 Institute of Engineering and Technology, Ahmedabad University, Gujarat, India

Noble metal nanoparticles (NPs) such as Pt, Pd and Au NPs are currently used in many fields, including catalysis, electronics, and biological technologies, owing to their unique size-dependent structures and properties. The development of noble metal NPs-based nanocomposites (NCs) for highly functional materials is a continuously expanding research topic. Here, we focus on clay which is a low-cost inorganic mineral with a layered structure and has generated significant interest because of its attractive properties such as ordered structure, intercalation capability, network formation[1] and high exchange capacity. Recently, we proposed a novel synthetic route to Pt/Clay NC system via clay-mediated in situ reduction under mild conditions, without using any organic modifiers[2]. The Pt/Clay NCs with Pt NPs (3-6 nm) (Figure1) anchored onto the clay nanoplates exhibit a very large surface area[2], high thermal stability[2,3] and outstanding catalytic activity for the reduction of 4-nitrophenol[2] and the carbon monoxide oxidation[4]. Subsequently, we reported the synthesis, structure, and properties of a novel hydrogel-based nanostructured Pt materials, Pt-NC gel[5], consisting of ultrafine Pt NPs (0.5-3 nm) strongly immobilized within a unique polymer-clay network (Figure 2). Ultrafine PtNPs were also obtained as a stable suspension from the NC gel, without any stabilizing agents. The combination of ultrafine Pt NPs and mechanically tough NC gel may open up new possibilities for designing functional Pt-gel materials. Furthermore, we reported a new claymediated one-pot preparation of various bimetallic core-shell nanocrystal-clay composites (Figure 3) with well-defined shapes and unique catalytic features[6]. In particular, the catalytic activity was significantly improved in Au(core)-Pd(shell)/Clay NCs. In the presentation, we discuss on the

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structures, stabilities and functions of noble metal nanoparticles (Pt, Pd, Au) in these NC (and gel) systems.

References [1] K. Haraguchi, Adv. Polym. Sci., 267 (2015) 187246. [2] D. Varade and K. Haraguchi, Langmuir, 29 (2013) 1977-1984. [3] D. Varade and K. Haraguchi, Phys. Chem. Chem. Phys., 15 (2013) 16477-16480. [4] D. Varade, H. Abe, Y. Yamauchi and K. Haraguchi, ACS Appl. Mater. Interfaces, 5 (2013) 11613-11617. [5] K. Haraguchi and D. Varade, Polymer, 55 (2014) 2496-2500. [6] D. Varade and K. Haraguchi, Chem. Commun., 50 (2014) 3014-3017.

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Figure 1.

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Figure 2.

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Figure 3.

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Tunable magnetoresistance in an asymmetrically coupled singlemolecule junction

Cyrus F Hirjibehedin c.hirjibehedin@ucl.ac.uk

London Centre for Nanotechnology, Department of Physics & Astronomy, Department of Chemistry, University College London (UCL), UK

References [1] B. Warner et al., Nature Nanotechnology 10, 259 (2015)

Figures

c)#2.0

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Phenomena that are highly sensitive to magnetic fields can be exploited in sensors and non-volatile memories. For example, a change in the electrical conductivity of a substance with magnetic field (i.e. magnetoresistance) is exploited in the read head of hard drives to detect changes in the orientations of the magnetic domains that store binary data. The scaling of such phenomena down to the single molecule level may enable novel spintronic devices. In this work, we report magnetoresistance in a single molecule junction (Fig. 1a,b) arising from a region of negative differential resistance (NDR) – a decrease in current with increasing applied voltage – that, as seen in Fig. 1c,d, shifts in a magnetic field at a rate two orders of magnitude larger than expected Zeeman shifts [1]. This sensitivity to the magnetic field produces two voltage-tunable forms of magnetoresistance, which can be selected via the applied bias. The NDR is caused by transient charging of an iron phthalocyanine (FePc) molecule on a single layer of copper nitride (Cu2N) on a Cu(001) surface, and occurs at voltages corresponding to the alignment of sharp resonances in the filled and empty molecular states with the Cu(001) Fermi energy. The voltage shift of the NDR with magnetic field, which inherently is on the scale of the Zeeman energy, is enhanced by the asymmetric voltage-divider effect. These results illustrate the impact that asymmetric coupling to metallic electrodes can have on transport through molecules, and highlight how this coupling can be used to develop molecular spintronic applications.

6T 4 .5 T

3T 1 .5 T

1.7

1 .8

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Figure 1. a) Schematic of FePc in an STM junction between the tip and Cu2N/Cu(001). b) STM topographic image of FePc molecules on Cu2N. c) Differential conductance spectroscopy measurements taken above the centre of an FePc molecule at 0 T (red) and 6 T (black). The magnetic field only moves features in the NDR region: other features in the spectrum remain constant. d) Same as (c) but with additional magnetic fields and over a smaller voltage range. (After [1])

* This work was done in collaboration with Ben Warner, Fadi El Hallak, Henning Prüser, John Sharp, Mats Persson, and Andrew Fisher.

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Redox-triggered, self-disassembled silica-based nanoplatform for intracellular imaging and drug delivery

Hsin-Yun Hsu, Xin-Chun Huang, Yun-Ling Luo

hyhsu99@nctu.edu.tw

Department of Applied Chemistry/Institute of Molecular Science, National Chiao-Tung University,No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan

With the advent of nanobiotechnology, research on cancer treatments has taken a new dimension, called theranostics, which combines diagnostics and therapeutics to improve the management of healthcare in clinics. In this regime, the development of molecular diagnostic tools and targeted therapeutics is inter-connected, aiming at smart drug release. Here we fabricated a redoxresponsive silica (ReSi)-based nanoplatform, of which self-disassembly could be triggered by intracellular thiols. We employed both the ReSi nanosphere and ReSifunctionalized gold nanoparticle (Au NPs) to demonstrate the drug delivery in liver carcinoma Hep G2 cells. The ReSi nanoshell exhibited tunable release of encapsulated drugs. At low GSH level (< 0.1 mM) only minute drug release occurred while at high intracellular GSH level (~1-10 mM) the destruction of disulfide-linked nanostructure was accelerated, leading to rapid release of large amount of drugs. Moreover, redox-responsive drug release could be monitored in situ by tracing the sites where fluorescence recovery and Au NPs aggregation occurred due to the destruction of the

networks. While it is relatively insensitive to minute amount of redox-active molecules; high intracellular GSH level could trigger the destruction of disulfidelinked silica nanoshell, resulting in an enhanced “Off−On” drug release. Our constructed redoxresponsive nanocarrier enables the optimization of drug efficacy with minimizing side effects and shall assist in improving the drug formulation and development process. This system provides great benefit for targeted drug delivery with high spatial/temporal resolution. Furthermore, we expect the Au NPassisted SERS optical monitoring and its future potential in photothermal therapeutics.

References [1] Chen YC, Huang XC, Luo YL, Chang YC, Hsieh YZ and Hsu HY, Sci. Technol. Adv. Mater., 14 (2013), 044407 [2] Huang XC, Wu LB, Hsu JF, Shigeto S, Hsu HY, Acta Biomater, (2015) [Epub ahead of print]; DOI:10.1016/j.actbio.2015.05.006

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Magnetoresistance in CVD-graphene on SiC 1

CNRS-Laboratoire Charles Coulomb (L2C), Montpellier, France American University of the Middle East (AUM), College of Engineering and Technology, Egaila, Kuwait 3 CNRS-Laboratoire de Photonique et de Nanostructures, Route de Nozay, 91460 Marcoussis, France 4 CNRS-CRHEA, rue Bernard Gregory, 06560 Valbonne, France 2

We investigate the electrical properties of graphene grown by Chemical Vapor Deposition (CVD) on the Si face of SiC substrates [1]. Magnetoresistance measurements have been performed under magnetic field in a wide temperature range. Depending on the growth condition, hole or electron doping can be achieved, down to a few 1011cm-2. Our CVD graphene samples are either standard epitaxial monolayer graphene on top of a ZLG and it corresponds to n-doped samples, or quasi-free standing graphene above a hydrogenated SiC substrate, where the ZLG is absent and it corresponds to p-doped samples [2].

Bilal Jabakhanji1,2, Dimitris Kazazis3, Adrien Michon4, Christophe Consejo1, Wilfried Desrat1 and Benoit Jouault1

bilal.jabakhanji@aum.edu.kw

References [1]

[2] [3] [4]

A. Michon et al., Appl. Phys. Lett., 97 (2010) 171909; A. Michon et al., J.Appl.Phys, 113 (2013) 203501 B. Jabakhanji et al., Appl. Phys. Lett., 89 (2014) 085422 B. Jabakhanji et al., Phys. Rev. B 90 (2014) 035423 I. V. Gornyi and A. D. Mirlin, Phys. Rev. B 69 (2004) 045313

In this talk, we examine the magnetoresistance results (for p- and n- doped samples) at intermediate magnetic field between weak localization and Landau quantization regimes to perform a systematic study of electron-electron interaction (EEI) [3]. Our work distinguishes the effect of EEI from additional quantum corrections to the longitudinal resistivity for arbitrary temperature. Furthermore, our results demonstrate a transition from the diffusive to the ballistic regime. This transition is not attributed to a modiďŹ cation of the number of multiplet channels participating to EEI due to inter- and intra- valley scattering. In graphene, EEI is specifically sensitive to the type of disorder which depends on both the graphene quality and the characteristics of the environment. Our analysis of EEI, more specifically in ballistic regime, is helpful to give an indication of the nature of disorder in grapheme. To describe our data, we rely on a recent theory [4] which predicts the EEI correction at all temperatures for both short- and long-range disorder.

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Graphene – silver nanoparticle interactions and their effect on Raman enhancement and transport properties

F. Jimenez-Villacorta1, E. Climent-Pascual1, R. RamirezJimenez2, J. Sanchez-Marcos3, C. Prieto1, A. de Andrés1

felixjv@icmm.csic.es

Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Madrid, Spain 2 Departamento de Física, Escuela Politécnica Superior, Universidad Carlos III de Madrid, Madrid, Spain 3 Departamento de Química-Física Aplicada, Universidad Autónoma de Madrid, Madrid, Spain

The modulation of optical and electrical properties of ultrafine (~4 nm) Ag nanoparticle/graphene/SiO2 hybrid material at low coverage is evaluated with gradual nanoparticle incorporation by the gas aggregation deposition technique.[1] The different contributing factors, such as doping, impurity scattering or strain, are assessed. Incorporation of Ag nanoparticles produce a very efficient n-type doping of graphene (~7.5 e- per particle) maintaining the mobility constant for particle coverage below ~0.3 monolayers. Doping efficiency at further coverage is determined by the probability for nanoparticles to be deposited in contact with graphene. The Fermi level upshift is modeled within the charged impurity scattering mechanism in the whole coverage range. A crossover to the regime where impurity scattering dominates is evidenced at large particle concentration. Surface-enhanced Raman scattering is detected in graphene phonons for coverage as low as 0.08 that correspond to ~100 nanoparticles at the laser spot. Small distortions of the graphene lattice (±0.012 %) induced by the nanoparticles overcome the predicted changes in Raman phonons related to carrier doping and originate I2D/IG damping. This evolution of physical properties with gradual incorporation of Ag nanoparticles is anticipated to provide valuable hints to tune the optic and electronic performance of these graphene-based hybrid systems.

References [1] F. Jiménez-Villacorta, E. Climent-Pascual, R. Ramírez-Jiménez, J. Sánchez-Marcos, C. Prieto and A. de Andrés, (submitted).

Acknowledgements This work is supported by MINECO (MAT2012-37276C03-01), from Comunidad de Madrid, project S2013/MIT-2740 (PHAMA_2.0-CM) and by the EU 7th Framework Program (grant agreement no.604391) “Graphene Flagship”.

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Atomic scale Boolean Logic gates

joachim@cemes.fr

Nanoscience Group & MANA Satellite CEMES-CNRS Toulouse A*STAR VIP Atom Tech, IMRE Singapore

At the atomic scale, surface Boolean logic gates can now be designed [1] and experimented [2] from inside a single molecule. They can now be constructed atom by atom using STM vertical single atom manipulations for example on an Si(100)H surface. After discussing why classical and semiclassical atomic scale circuits [3] may not be very practical for beneficiating from the anticipated atom circuits computing power [4], we will present the design rules of the quantum Hamiltonian computing (QHC) approach [5] applied to atom circuits Here, the possibility offered by the QHC approach for a logic function complexity increase is a very good example on how to minimize the interconnection problem that is the number of “classical to quantum” and “quantum to classical” conversions steps required to pass from the atomic scale of an atom circuit to the nanoscale and more in full planar technology. The first practical construction of an atomic scale QHC Boolean logic gate will be presented [6]. A first technological roadmap will also be presented to finally back interconnect and encapsulate such circuits to produced molecular chips for a future planar technology [7].

TNT2015 toulouse (france)

C. Joachim

References [1] C. Joachim, N. Renaud and M. Hliwa, Adv. Materials, 24, 312 (2012). [2] W.H. Soe and coll. Phys. Rev. B, 155443 (2011). [3] H. Kawai, and coll., J. Phys. Cond. Mat., 24, 095011 (2012). [4] Y. Wada and coll. US Patent n°: 5,561,300, Oct. 1st, 1996. [5] N. Renaud, M. Hliwa and C. Joachim Phys. Chem. Chem. Phys., 13, 14404 (2011). [6] M. Kolmer and coll., Nanoscale, submitted (2015). [7] C. Joachim, Springer Series: “Advances in Atom and Single Molecule Machines” Vol. VII “Nanopackaging”, in press (2015).

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The beauty of quantum transport in graphene grown on SiC

Benoit Jouault

Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS-UniversitĂŠ de Montpellier, Montpellier, France

The famous integer quantum Hall effect (QHE), discovered in 1980, is one of the most fascinating quantum effects existing in condensed matter physics. It appears in a strong transverse magnetic field, as the Hall resistivity of a two dimensional electron gas (2DEG) develops plateaus at values quantized in units of h/eÂ˛. Because of this unique relation between electrical resistance and fundamental physical constants, the QHE in GaAs heterostructures is used in modern metrology to define electrical resistance standards. The discovery of the QHE in graphene a few years ago sparked an immediate interest. In graphene, the massless nature of the charge carriers leads to a Landau level spectrum with an energy gap between the first adjacent levels which is five times larger than that in GaAs for magnetic fields around 10 T and twenty times larger around 1 T. This implies that the QHE in graphene can be observed at much reduced magnetic fields or at much higher temperatures. The QHE is therefore expected to be more robust in graphene. This has been confirmed by recent experimental works, where QHE was observed in monolayer graphene on SiC with homogeneous carrier concentration, low carrier densities and high mobility - three prerequisites for metrology. Motivated by these perspectives, we will show some of our recent results obtained with graphene grown on SiC substrates. We have shown that in these samples, little changes in temperature during the growth can trigger the carrier concentration [1].

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Monolayer graphene films are obtained, homogeneous at the centimeter scale, allowing precise transport measurements. The study of the quantum corrections at low magnetic fields reveals that various scattering mechanisms are at play in these devices [2]. At higher fields, the stability of the quantum Hall plateaus with respect to current, temperature and magnetic field is remarkable and extends over more than 70 T. This stability is probably linked with both charge transfer and/or some specific disorder. Finally, we will present the best metrological results obtained with these samples [3]. They show exceptionally good metrological properties, with relative accuracies of the quantized resistance of the order of 10-9.

References [1] B. Jabakhanji, A. Michon, C. Consejo, W. Desrat, M. Portail, A. Tiberj, M. Paillet, A. Zahab, F. Cheynis, F. Lafont, et al., Phys. Rev. B 89, 085422 (2014). [2] B. Jabakhanji, D. Kazazis, W. Desrat, A. Michon, M. Portail, and B. Jouault, Phys. Rev. B 90, 035423 (2014). [3] F. Lafont, R. Ribeiro-Palau, D. Kazazis, A. Michon, O. Couturaud, C. Consejo, T. Chassagne, M. Zielinski, M. Portail, B. Jouault, et al., Nature Commun. 6, 6806 (2015)

TNT 2015 toulouse (france)

Oxydation route determines the magnetic and relaxivity properties of iron oxide nanocrystals: toward highly efficient MRI contrast agent

Gérald Casterou1,2, PierreAntoine Eliat3, Fabienne Gauffre2, Myrtil L. Kahn1

myrtil.kahn@lcc-toulouse.fr

Laboratoire de Chimie de Coordination-CNRS, 205 route de Narbonne, 31077 Toulouse, France 2 Institute of Chemical Sciences of Rennes, University of Rennes/CNRS, France 3 PRISM - Biosit CNRS UMS 3480, INSERM UMS 018, Rennes, France

The synthesis of ultrasmall superparamagnetic iron oxide nanocrystals (USPIO) with controlled size distribution and crystallinity has been a constant challenge for advanced applications such as MRI or hyperthermia, which require specific magnetic features.[1-3] Using an organometallic approach, we investigate independently the hydrolysis and oxidation steps in the synthesis of USPIO. The USPIO were investigated by a variety of analytical techniques and we demonstrate that the oxidation route influences the structural and magnetic properties of the USPIO. In particular, the property most directly related to the efficiency of MRI contrast agents, the magnetic relaxivity, appears to depend critically on the elaboration process. Thus, starting from highly homogeneous wüstite (Fe1-yO) Ncs, the selection of the oxidation pathway led to maghemite (γ-Fe2O3) Ncs optimized for MRI. Finally, the USPIO are assembled into SPIO (superparamagnetic iron oxide) aggregates of ca 150 nm, which are water dispersable and exhibit relaxivity values ca 4 time higher than the commercial Feridex® MRI contrast agent. Such SPIO aggregates are moreover stable in a lot of different physiological media (beef blood, beef serum, foetal

calf serum, DMED cell culture). These SPIO aggregates consequently exhibit a significant decrease of the signal even with a very short echo time of 8 ms which is of paramount importance in clinical trials because it significantly decreases the duration of the MRI measurement and can significantly improve the patient’s well-being.[4]

References [1] Kim, S.-G.; Harel, N.; Jin, T.; Kim, T.; Lee, P.; Zhao, F. NMR Biomed. 26 (2013) 949. [2] Lodhia, J.; Mandarano, G.; Ferris, N.; Eu, P.; Cowell, S.; Davidson, R. Biomed. Imaging Interv. J. 6 (2010) e12. [3] Laurent, S.; Forge, D.; Port, M.; Roch, A.; Robic, C.; Vander Elst, L.; Muller, R. N. Chem. Rev. 108 (2008) 2064. [4] Gérald Casterou, Vincent Collière, Pierre Lecante, Yannick Coppel, Pierre-Antoine Eliat, Fabienne Gauffre and Myrtil L. Kahn (2015) soumis

Figures

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Surface States in Weyl Semimetal Superconductors

Hsien-chung Kao

hckao@ntnu.edu.tw Department of Physics, National Taiwan Normal University, 88 Section 4, Ting-Chou Road, Taipei, Taiwan

It has been pointed out that open Fermi arcs may exist on certain surfaces of Weyl semimetal. Recent studies show that more exotic surface states may appear on the interface between Weyl semimetal superconductors and ordinary insulators. We study the effect on the surface states of the interface when various type of insulators are considered.

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References [1] Bo, Lu, Keiji Yada, Masatoshi Sato, and Yukio Tanaka, Physical Review Letters, 114 (2015) 096804. [2] A.A. Burkov and Leon Balents, Physical Review Letters, 107 (2011) 127205.

TNT2015 toulouse (france)

Optically Transparent FTO-Free Cathode for Dye-Sensitized Solar Cells

Ladislav Kavan1,2, Paul Liska2, Shaik M. Zakeeruddin2 and Michael Graetzel2

J. Heyrovský Institute of Physical Chemistry, v.v.i., Academy of Sciences of the Czech Republic, Dolejškova 3, CZ-18223 Prague 8, Czech Republic 2 Laboratory of Photonics and Interfaces, Institute of Chemical Sciences and Engineering, Swiss Federal Institute of Technology, CH-1015 Lausanne, Switzerland

A traditional counterelectrode in dye-sensitized solar cell (DSC) is platinized F-doped SnO2 (FTO). However, the cost of FTO glass is estimated to be about >20-60% of the cost of the DSC-module, which is a strong motivation for FTO replacement by cheaper materials. Recently, nanocarbon and graphene-based materials attracted considerable attention, particularly for Co-mediated DSCs. Another alternative, which also works well with the I3-/I- redox mediator, is the woven fabric consisting of transparent PEN fibers in warp and electrochemically platinized tungsten wires in weft. This electrode outperforms the thermally platinized FTO in serial ohmic resistance, Rs (1.5 vs. 8.2 Ωcm2), charge-transfer resistance for triiodide reduction (0.59 Ωcm2 vs. 0.76 Ωcm2) and offers comparable or better optical transparency in the visible and particularly in the near-IR spectral region (≈80%). The Pt-W/PEN cathode exhibits good stability

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during electrochemical load with the maximum (diffusion-limited) current both in cathodic and anodic directions, and during long term (≈month) storage at open circuit. The practical dye-sensitized solar cells with either Pt-W/PEN or Pt-FTO cathodes show similar performance, confirming that the former is a promising alternative for replacement of conductive glass in the DSC counterelectrodes.

Acknowledgement: This research was supported by the Grant Agency of the Czech Republic (contract No. 13-07724S), by the Swiss Commission for Technology and Innovation (CTI) project No. 16452.2 PFNM-NM and by the European Research Council through the Advanced Research Grant no. 247404 ‘Mesolight’.

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Bottom-up formation of molecular wires on a semiconducting oxide: Aryl halides covalent coupling controlled by surface hydroxyl groups on rutile TiO2 surfaces

Marek Kolmer1, Rafal Zuzak1, Amir A.A. Zebari1, Szymon Godlewski1, Jakub S. Prauzner-Bechcicki1, Witold Piskorz2, Filip Zasada2, Zbigniew Sojka2, David Bléger3, Stefan Hecht3, Marek Szymonski1

Centre for Nanometer-Scale Science and Advanced Materials, NANOSAM, Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, Poland 2 Faculty of Chemistry, Jagiellonian University, Krakow, Poland 3 Department of Chemistry, Humboldt-Universität zu Berlin, Berlin, Germany

Molecular nano-architectures formed by the onsurface chemical reactions have attracted great attention over the last few years [1-3]. The bottomup strategies allow assembling of covalently coupled molecular structures of well-defined morphologies, including: molecular wires, 2D molecular networks, or confined graphene nanostructures. So far, surfaces of selected noble metals have been mostly used as substrates. Recently we could demonstrate for the first time the feasibility of the on-surface covalent coupling of aryl halide precursors on a semiconducting oxide. Low temperature STM (LT-STM) studies and DFT-D modelling showed that thermally activated 10,10’-dibromo-9,9’-bianthryl (DBBA) monomers form polyanthrylene chains on the rutile TiO2(011)(2x1) surface [4]. Following our recent work, here, we report on the role of surface hydroxyl groups in the on-surface polymerization on rutile TiO2(011) and demonstrate univocally that OH groups are in this case essential for the reaction to occur [5]. We show that the polymerization of diiodoterfluorene (DITF)

marek.kolmer@uj.edu.pl

molecules proceeds most effectively when the reduced TiO2(011) is prepared with a moderate density of surface hydroxyls(~5% coverage), leading to formation of long molecular wires. Increasing the density of the surface hydroxyls (to ~20%) by surface exposure to atomic hydrogen results in formation of shorter oligomers, whereas the hydroxyl-free surface (<0.5%) suppresses the polymerization reaction completely. These results are in agreement with the recently proposed C-C coupling mechanism, which involves proton transfer from a surface hydroxyl group to the precursor molecule [4,5].

References [1] [2] [3] [4]

L. Grill et al., Nat. Nanotechnol. 2 (2007) 687 J. Cai et al., Nature 466 (2010) 470 L. Lafferentz et al., Nat. Chem. 4 (2012) 215 Kolmer et al., Angew. Chem. Int. Ed. 52 (2013) 10300 [5] Kolmer et al., Chem. Comm. (2015) DOI: 10.1039/C5CC02989A

Figure 1. Polymerizing the DITF monomers on rutile TiO2(011) surfaces with varying hydroxyl groups coverage [5].

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Hollow boron nitride spherical nanoparticles: synthesis, structure and applications

A. Kovalskii1, A. Matveev1, O. Lebedev2, I. Sukhorukova1, K. Firestein1, A. Steinman1, D. Shtansky1, D. Golberg3

National University of Science and Technology “MISIS”, Moscow, Russia CRISMAT, UMR 6508, CNRS-ENSICAEN, 6Bd Marechal Juin, Caen 14050, France 3 National Institute for Materials Science (NIMS), Ibaraki, Tsukuba, Japan 2

Nanoparticles of spherical morphology find many areas of application now, significant usages are at the moment are actively developing in biological, medical and ecological fields. Due to excellent physical-chemical properties of boron nitride, applications of its nanospheres can significantly expand areas of utilization. The question of present interest in regards of such nanoparticles is the development of high yield synthetic method which may produce particles of homogenous size. In the present work the new nanomaterial consisting of hollow spherical BN nanostructures with smooth and petal-like surfaces was obtained for possible applications in composite materials and as drug delivery containers. Synthesis of BN nanospheres with an external diameter of 80-250 nm was carried out by CVD method using boron oxide vapor and flowing ammonia in a BN ceramic reactor placed in a vertical induction furnace. Three types chemical compound powders with a different ratio of constituents were used as a source of B2O3 vapor: FeO+MgO+B, SnO+MgO+B and H3BO3+MgO+B. The temperature in a location area of the precursor was varied over the range of 1200-1430°C. Synthesis was carried out for 200-420 min. Products of syntheses were collected on the walls of BN crucible in a low temperature zone out of BN reactor as a thick light snow-white material. Typically, using 10 g of the precursor was enough to synthesize about 250-400 mg of the material in 420 min.

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andreykovalskii@gmail.com

The morphology of synthesized products and their elemental composition were studied using a scanning electron microscope JEOL JSM-7600F equipped with the EDX detector. As was revealed by SEM analysis, the synthesized powders obtained in all experimental conditions consist of agglomerates of spherical nanoparticles with a hollow core and an average size 80-200 nm (Fig. 1a, b), and a petal-like surface made of nanosheet-like flakes. After some syntheses hollow spherical particles with smooth surface were also observed. The synthesized products were proved to be of the BN phase with a hexagonal structure using EDX, XRD and FTIR methods. It was shown that the experimental conditions mostly affected the impurity content and the yield of the nanomaterial product. Low-magnification (Fig. 1c, Fig. 2a, b), and highresolution TEM investigations of synthesized nanoparticles were carried out and it was demonstrated that agglomerates consist of round shape nanoparticles. The corresponding SAED pattern taken from the number of BN nanoparticles contains two diffuse rings with d-spacings roughly corresponding to the BN interplanar spacings (d002 and d100). TEM analysis shows (Fig. 2b) that nanoparticles exhibit a hollow spherical central part and a petal-like surface due to exposed BN layers at the side area. On the HRTEM image of surface area (Fig. 2c) one can observe nanospheres build up from exposed BN layers with typically two to six stacked sheets.

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Figures (a)

(b)

(c)

Figure 1. SEM image of agglomerates of (a) petal-like and (b) smooth spherical BN nanoparticles with an average size 100-200 nm. (c) LM-TEM image of petal-like and smooth BN nanospheres.

Figure 2. (a, b) BF LM-TEM image of petal-like BN nanospheres; (c) HRTEM image of the side region of a BN nanosphere.

The applications of obtained spherical BN nanoparticles for the reinforcement of composite materials and as a drug delivery containers are demonstrated.

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TNT2015 toulouse (france)

Diamond and lonsdaleite 13C and 12C formation in a diamond anvil highpressure cell Technological Institute for Superhard and Novel Carbon Materials (TISNCM), 7a Centralnaya str., Troitsk, Moscow, 142190, Russia

The behaviour of solids under extreme conditions is of great importance and interest for modern physics. A diamond anvil cell (DAC) is a device used in scientific experiments. It allows compressing a small (sub-millimeter sized) piece of material to extreme pressures. This work was aimed at obtaining diamond from graphite in a diamond anvil cell (DAC) using high pressure and shear strain - a task that the science has so far mostly failed to implement,- and studying the features of this transformation by highresolution TEM, EELS-spectroscopy, and Ramanspectroscopy, as well as comparing the different mechanisms of graphite-to-diamond transformation. Examinations were carried out using a JEM-2010 high-resolution transmission electron microscope and a JSM-7600F scanning electron microscope. The particles of diamond and its allotrope lonsdaleite were prepared by graphite treatment in a high-pressure chamber made of diamond anvils (DAC), at room temperature and without catalyst. For greater reliability of the results, the experiments were made using 13C graphite, whereas the diamond anvils were made of 12C carbon isotope. 13C graphite was selected due to the fact that during processing, the anvil may slightly crumble and its dust particles can penetrate the sample. The synthesis was carried out under high pressures and shear deformation. Under some

Kulnitskiy B.A., Blank V.D., Perezhogin I.A., Tyukalova E.V., Denisov V.N., Kirichenko A.N. boris@tisnum.ru

processing conditions, for the first time the carbon onions were obtained during graphite treatment in a diamond anvil high-pressure chamber under conditions of shear deformation at room temperature. It has been determined that the number of layers in the onions increases with the increase of pressure and shear values. After treatment in the diamond chamber with a shear, a sequence of structures was observed depending on treatment conditions: hexagonal graphite - rhombohedral graphite - diamond or hexagonal graphite - onions - diamond. Along with diamond, some fragments and individual particles of lonsdaleite were found (a diamond allotrope different in packing). In the laboratory, lonsdaleite is prepared together with diamond in conditions of static and dynamic pressures and temperatures. Diamond formation is confirmed by high-resolution TEM (Figure 1a), and by the EELS spectra (Figure 1b). The Raman spectra of the 13C showed that there was a weak broad band at 1265 cm-1. Given that the position of the 13C diamond line is 1280 cm-1, and the crystallite size reduction leads to its broadening and shift towards the lower wave numbers, we attribute the 1265 cm-1 line to the appearance of diamond nanocrystals with a particle size of about 3-4 nm in accordance with the phonon-confinement model.

Figures 13

Figure 1. a) A high-resolution image of a C diamond particle after high-pressure-shear 13 deformation treatment of C graphite. Two {111} diamond planes are shown. The angle o between these planes is about 70 . b) EELS spectra of a), the arrow indicates a peak corresponding to the diamond structure

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Subsurface Epitaxial Growth of Hidden Co Nanoclusters

O. Kurnosikov, T. Siahaan, H.J.M. Swagten, B. Koopmans

Eindhoven University of Technology, Den Dolech 2, Eindhoven, The Netherlands

o.kurnosikov@tue.nl

A new subsurface growth mode in the Co-Cu system is reported [1]. A direct subsurface growth of Co nanoclusters by depositing Co atoms on the Cu(001) surface in a single stage at elevated temperature is achieved. At the temperature range close to 650K Co is able to diffuse easily a few atomic layers below the Cu surface whereas a remarkable diffusion in the bulk is still not activated (Fig.1). Co accumulates near the surface and forms the subsurface clusters while Co on the surface or embedded in the surface is presented insignificantly. The resulting subsurface Co nanoclusters are located 2 monolayers (ML) deep below the atomically flat surface of Cu(001). Although the formed nanoclusters are hidden below the copper surface they can still be detected using STM/STS. The detection of hidden subsurface Co clusters is achieved by the analysis of the subatomic deformation of the Cu(001) surface, which is in the range of 20 pm, as well as via local variations of surface electron density of copper above the clusters (Fig.2). Monitoring the evolution of the surface depressions and STS spectra versus the deposition dose the shape of subsurface Co nanoclusters is deduced: they are typically 5-10 nm in lateral size but only 2 to 3 ML in thickness. The thickness of the nanoclusters does not evolve significantly under a heat treatment. The kinetics of growth indicates a nucleation dead-time. A simple model is implemented to describe the growth kinetics. The results in this study reveal that intense processes of diffusion, nucleation, and growth take place down to 1 nm below the surface, thus defining the near-surface region.

References [1] T. Siahaan, O. Kurnosikov, H. J. M. Swagten, and B. Koopmans, Phys. Rev. B, 90 (2014) 165419.

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Figures

Figure 1. Process of subsurface nanoclusters formation. (a) Beginning of Co deposition on a hot Cu(001) substrate. (b) Incorporation and accumulation of Co in the near-surface region. (c) formation of an initial Co cluster. (d) Further growth of the next layer of the clusters, accompanied by Co segregation (blue and red arrows).

Figure 2. (a) A typical STM image (18 Ă&#x2014; 18 nm ) of the atomically flat Cu(001) surface with a local depression induced by a subsurface Co cluster. The depression depth across the blue cross-section line is of about 20 pm. The tunnelling set point is (0.2 V, 1 nA). (b) The surface differential conductance map (STS mapping) corresponding to the area shown in (a) at the same tunnelling set point shows the enhanced conductance above the hidden Co nanocluster. The ripple observed in both types of images originates from single Co atoms dissolved near-surface.

TNT2015 toulouse (france)

Covalent heterostructure based on self-decorated MoS2 and graphene

Dmitry G. Kvashnin1,2, Gotthard Seifert3, Leonid A. Chernozatonskii1

dgkvashnin@gmail.com

Emanuel Institute of Biochemical Physics RAS, Moscow, Russia National University of Science and Technology MISiS, , Moscow, 119049, Russian 3 Technische UniversitĂ¤t Dresden, Dresden, Germany 2

Investigations of two dimensional materials are the most promising and developing areas in science and technologies nowadays. Graphene and MoS2 are the two intensive study materials. Graphene is semimetal with zero band gap displays amazing electronic, mechanical and optical properties. MoS2 belongs to the family of transition metal dichalcogenides with semiconductor bulk band gap about 1.6 eV depending of the thickness. Complementary physical properties of graphene and MoS2 naturally allow combining these materials to create heterostructures with unusual properties. Set of numbers of the layers of various compounds allows us to create heterostructures by combining the layers between each other. Only the drawback of obtained heterostructure is the weak van der Waals interaction between the layers. To improve a weak interaction an individual metal atoms could be adsorbed on the layers surface before the creation of the heterostructure. Here the detailed investigation of novel covalent heterostructures based on graphene and MoS2 was carried out using ab initio calculations. Firstly the decoration process of MoS2 by Mo adatoms (self-

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decoration) was studied. It was found the strong binding between the MoS2 layer and molybdenum adatoms which states about energy favorability of adsorption onto MoS2 surface. Further investigation of step by step decoration process and migration barrier of adatom on the MoS2 surface to understand the origin of strong binding with taking into account inertness nature of MoS2 layer was carried out. Electronic properties were also studied during the decoration process. Finally the electronic properties of covalent heterostructure were studied. It was found that dz2 orbitals of Mo adatoms between the graphene and MoS2 surfaces are responsible for the formation of the conduction channel. This work was supported by the Russian Scientific Foundation (project no 14-12-01217). We are grateful to the 'Chebishev' and 'Lomonosov' supercomputers of Moscow State University and the Joint Supercomputer Center of the Russian Academy of Sciences for the possibility of using a cluster computer for our quantum-chemical calculations.

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Ultrathin Au nanowires: towards 1D electronic properties

L.-M. Lacroix1, M. ImperorClerc2, R. Arenal3,4, B. Pansu2, L. Ressier1, P. Moutet1, G. Viau1

UniversitĂŠ de Toulouse, INSA, UPS, LPCNO (Laboratoire de Physique et Chimie des Nano-Objets), F-31077 Toulouse, France; CNRS; UMR 5215 ; LPCNO, Toulouse, France 2 Laboratoire de Physique de Solides, UMR 8502, UniversitĂŠ Paris-Sud, Orsay, France 3 Laboratorio de Microscopias Avanzadas (LMA), Instituto de Nanociencia de Aragon (INA), U. Zaragoza, Zaragoza, Spain 4 Fundacion ARAID, 50004 Zaragoza, Spain

Recently, ultrathin gold nanowires (NWs) prepared by reduction of HAuCl4 in solution of oleylamine (OY) attracted lots of interest due to their size homogeneity (diameter 1.7 nm, micrometer length) [1] with application as foldable optoelectronics membranes [2,3] or elastic coiled springs [4]. Their unique 1D feature confers them remarkable conductivity properties such as quantum phenomena at room temperature [5,6] but the study of the electronic properties of single NW still remains a technological challenge and requires a good understanding of their physical properties. SAXS (Small Angle X Ray Scattering) and XPS studies allowed us to describe the self-assembly of ultrathin Au NWs into an expended hexagonal super-lattice with a parameter of 9.7 nm well explained by a oleylammonium chloride (OY+ Cl-) / oleylamine (OY) bilayer at the surface of each NW and suggests a 1D micellar growth mechanism [7]. To confirm this hypothesis, SANS (Small Angle Neutron Scattering) and NMR studies have been recently performed. We showed that Au NWs solubilized in hexane exhibit a net negative charge in presence of strong electric field, due to the reorganization of the OY+ Cl- ions. Thus, the design of predefined positive

lmlacroi@insa-toulouse.fr

patterns using AFM nanoxerography, enabled us to deposit isolated Au NWs thanks to a Coulomb force directed assembly. The stability of single Au NWs under external stimuli was studied in-situ by realtime HAADF-STEM [8]. Under electron beam irradiation, Au NWs tend to fragment into stable islands through the ejection of atoms and the appearance of quantized atomic channels as transient state. Modification of the wire surface energy, through ligands exchange process, could enable to further stabilize the single-atom thick chains, opening great perspective for further electronic transport measurement on isolated Au NWs deposited by nanoxerography.

References [1] H. Feng et. al, Chem. Comm., 1984 (2009) [2] Y. Chen et al., Adv. Mater. 25 (2013) 80 [3] A. Sanchez-Iglesias et al., Nano Lett. 12 (2012) 6066 [4] J. Xu et al. J. Am. Chem. Soc. 132 (2010) 11920 [5] S. Pud et al. Small, 9 (2013) 846 [6] A. Loubat et al. Nano Res., 6 (2013) 644 [7] A. Loubat et al. Langmuir, 30 (2014) 4005 [8] L.-M. Lacroix, A. Arenal, G. Viau, J. Am. Chem. Soc., 136 (2014) 13075

Figures

Figure 1. a) TEM and b) HAADFSTEM images of Au NWs. Singleatom thick chain formed during wire fragmentation under Ebeam irradiation.

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TNT2015 toulouse (france)

Electron-phonon interaction and quantum interference in molecular junctions

P. Lafarge1, C. Bessis1, M. L. Della Rocca1, C. Barraud1, P. Martin2, J.-C. Lacroix2

Université Paris Diderot, Sorbonne Paris Cité, MPQ, UMR 7162 CNRS, Paris, France Université Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086 CNRS, Paris, France

Recent experiments have highlighted the role of destructive quantum interference in transport through single molecule devices [1,2,3] or large area molecular junctions [4]. The ability to control the wave nature of electrons at the molecular level is a new development in molecular electronics that could improve knowledge and control of electron transport through molecular systems. Crossconjugated molecules, such as anthraquinone, can behave as molecular quantum interferometers where the interference is due to different paths through the molecular orbitals of the molecule. The signature of quantum interference in molecular system is an antiresonance in the electron transmission function resulting in a strong suppression of conductance at low bias voltage. However, most of the experiments have been conducting in ambient conditions and the influence of temperature and the role played by the excitations on this effect are still not known. I will present our measurements of the influence of electron-phonon interaction on quantum interference in anthraquinone molecular layers embedded in large-area solid-state devices. We have found that the conductance is strongly dependent both on voltage and on temperature. The temperature dependence and the shape of the conductance curves are well accounted by a theoretical model including electron-phonon interaction in agreement with recent theoretical results [5]. The temperature effect is due both to the broadening of the Fermi functions of the leads and to the electron-phonon interaction. Signatures of the phonon energies are visible in the conductance curve at low temperature. We believe that our findings open up new avenues in engineering the electronic properties of molecular devices.

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philippe.lafarge@univ-paris-diderot.fr

References [1] C. M., Guedon, H. Valkenier, T. Markussen, K. S. Thygesen, J. C. Hummelen, S. J. van der Molen, Nat. Nanotechnol., 7 (2012), 305. [2] C. R. Arroyo, R. Frisenda, K. Moth-Poulsen, J. S Seldenthuis, T. Bjørnholm, H. S.J van der Zant Angew. Chem. Int. Ed., 52 (2013), 3152. [3] A. Batra,J. S. Meisner,P. Darancet,Q. Chen,M. L. Steigerwald,C. Nuckolls, L. Venkataraman Faraday Discussions, 174 (2014), 79. [4] V. Rabache, J. Chaste, P. Petit, M.L. Della Rocca, P. Martin, J.C. Lacroix, R.L. McCreery, P. Lafarge J. Am. Chem. Soc. 135 (2013), 10218. [5] T. Markussen, T. S. Thygesen, Phys. Rev. B 89 (2014), 085420.

Figures

Figure 1. Measured conductance as a function of applied voltage of an anthraquinone based junction for temperatures varying between 11 k and 250 K.

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Graphene and Nanotechnologies contributions to SPR in Sensia's experience

Iban Larroulet

SENSIA, Spain

sensia@sensia.es

SENSIA is a technological leader company in the field of analytical instrumentation based on SPR (Surface Plasmon Resonance), for life sciences laboratories and environmental measurements. Sensia has developed in 2014 an innovative SPR (Surface Plasmon Resonance) solution, using graphene biosensing and introducing on the market the first available commercial graphene biosensors, in a device whose microfluidics have been conceived to withstand the use of bacteria and/or of nanoparticles. The conception of the optical system enables extreme versatility, allowing the indifferent use of gold biosensors, of graphene coated biosensors, and of silica coated biosensors, with no required change of geometry of the optical platform, although the refractive indexes change.

References [1] Oleksandr Zagorodko, Jolanda Spadavecchia , Aritz Yanguas Serrano ยง, Iban Larroulet , Amaia Pesquera, Amaia Zurutuza, Rabah Boukherroub , and Sabine Szunerits; Anal. Chem., 2014, 86, 11211-11216. PDF [2] Kostiantyn Turcheniuk, Charles-Henri Hage, Jolanda Spadavecchia, Aritz Yanguas Serrano, Iban Larroulet, Amaia Pesquera, Amaia Zurutuza, Mariano Gonzales Pisfil, Laurent Heliot, Julie Bouckaert, Rabah Boukherroub and Sabine Szunerits; J. Mater. Chem. B, 2015, 3, 375 [3] Oleksandr Zagorodko, Julie Bouckaert, Tetiana Dumych, Rostyslav Bilyy, Iban Larroulet, Aritz Yanguas Serrano, Dimitri Alvarez Dorta, Sebastien G. Goui , Stefan-Ovidiu Dima, Florin Oancea, Rabah Boukherroub and Sabine Szunerits; Biosensors 2015.

Several strategies of immobilization can be therefore used. The combination of graphene biosensors together with nanoparticles in Sensia's SPR device, the Indicator-G, leads to new unattained limits of detection, getting into the attomolar range, therefore bringing in new applications and diagnostic possibilities.

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TNT2015 toulouse (france)

Progress in single layer silicene functionalization and in multilayer germanene growth

G. Le Lay1, E. Salomon1, D. Beato-Medina1, M.E. Dávila2 and T. Angot1 guy.lelay@univ-amu.fr

Aix Marseille Université, CNRS, PIIM UMR 7345,13397 Marseille, France Instituto de Ciencia de Materiales de Madrid-ICMM-CSIC, C/Sor Juana Inés de la Cruz, 3 Cantoblanco, 28049-Madrid, Spain

Silicene and germanene are emergent novel artificial two-dimensional (2D) materials that might rival graphene for logic applications in electronics [1]. Silicene has attracted enormous interest since 2012 after publication of our seminal paper on the epitaxial synthesis of the archetype 3 x 3 reconstructed monolayer silicene phase in perfect coincidence with a 4 x 4 cell on a silver (111) substrate [2]. Just recently, ordered and reversible hydrogenation of this phase has been achieved, first in Beijing [3], next at the PIIM Lab in Marseille, where high resolution spectroscopic results have been added [4]. Strikingly, the first silicene FET with ambipolar characteristics has been fabricated [5]. We have also synthesized multilayer silicene, which is self-protected in ambient air, on a silver template [6] and single layer germanene, predicted to be a robust 2D topological insulator at nearly room temperature, on a gold substrate [7]. Few months later, single phase monolayer germanene was synthesized in Mulhouse on an aluminum one at just 80°C [8]. In my talk, I will summarized those results and present new results on multilayer germanene [9].

TNT2015 toulouse (france)

References [1] G. Le Lay, Nature Nanotechnology 10 (2015) 202 [2] P. Vogt, P. De Padova, C. Quaresima, J. Avila, E. Frantzeskakis, M. C. Asensio, A. Resta, B. Ealetand G. Le Lay, Phys. Rev. Lett. 108 (2012) 155501 [3] J. Qui et al., Phys. Rev. Lett., 114 (2015) 126101 [4] E. Salomon, D. Beato-Medina, G. Le Lay and T. Angot, in preparation. [5] L. Tao, E. Cinquanta, D. Chiappe, C. Grazianetti, M. Fanciulli, M. Dubey, A. Molle and D. Akinwande, Nature Nanotechnol., 10 (2015) 227 [6] P. De Padova, C. Ottaviani, C. Quaresima, B. Olivieri, P. Imperatori, E. Salomon, T. Angot, L. Quagliano, C. Romano, A. Vona, M. MunizMiranda, A. Generosi, B. Paci and G. Le Lay, 2D Materials 1, 021003 (2014). [7] M. E. Dávila, L. Xian, S. Cahangirov, A. Rubio and G. Le Lay, New Journal of Physics 16, 095002 (2014). [8] M. Derivaz et al., Nano Lett., 15, 2510 (2015). [9] M.E. Dávila and G. Le Lay, in preparation

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Hybrid Organic/Inorganic Nanostructures for Energy Conversion and Storage Devices on Flexible Substrates

Philippe LeclĂ¨re Philippe.LECLERE@umons.ac.be

Laboratory for Chemistry of Novel Materials, Center for Innovation and Research in Materials and Polymers (CIRMAP), Research Institute for Materials Science and Engineering, University of Mons (UMONS), Place du Parc 20, B-7000 Mons, Belgium.

Research on existing and emerging energy conversion and storage technologies is pivotal to solve the economic and environmental challenges facing the energy sector. The general approach to meet both of these challenges is by exploring novel materials and device designs, such as those recently developed in organic and hybrid photovoltaic solar cells. In addition, progress in storing the produced energy is equally important. Interestingly, the co-integration of photovoltaic technologies and Li-ion batteries (LiBs) is expected to mark a turning point for nomade devices. However, to further improve the efficiency and stability of these devices, a better understanding of the device physics and how structural changes affects charge generation and transport at the nanometer scale is mandatory.

interconnected metal nano-shells to improve the performance of Li-ion batteries will be also presented.

In this context, we used a range of state-of-the-art scanning probe microscopy techniques to characterize the morphological, electrical and mechanical properties of solid hybrid systems which could be considered for the realization of transparent and flexible photovoltaic cells and lithium ion batteries. Here, we report on our approach to develop new grid-like hybrid three-dimensional architectures and devices based on semiconductor nanostructures or metal oxides and conjugated polymer materials. We demonstrate the use of a photoconductive Atomic Force Microscopy and Kelvin Probe Force Microscopy to locally study the electrical properties of prototype hybrid and organic solar cells. Results of the use of new gridlike electrodes coated with electrically

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TNT2015 toulouse (france)

FIB etching of h-BN membranes for osmotic energy conversion

S. Linas1, R. Fulcrand2, B. Poinsot1, F. Cauwet1 and A. Brioude1

LMI, Laboratoire Multimateriaux et interfaces, 22 avenue Gaston Berger, 69622 Villeurbanne, France 2 ILM, Institut lumière matière, 10, rue Ada Byron, 69622 Villeurbanne, France

Confinement of fluids in channels is a versatile topic involved in promising applications such as energy generation [1], ultra-filtration [2] or DNA sequencing [3] . As the fluid confinement reaches the nano-scale, new phenomena arise and the nature of channels’ walls gain more and more influence on the behavior of the fluid. Experimentally, nanotubes are an ideal nano-object for nanofluidics, offering channels from few to tens of nanometers in diameter over micrometer length-scale. Compared to carbon nanotubes (CNTs), boron nitride nanotubes (BNNTs) possess many advantages such as an improved chemical stability, better biocompatibility or a resistance to oxidation at high temperature. By highlighting the importance of the nature of the walls of the channels, BNNT are seen to be superior to CNT for nanofluidic applications: molecular dynamics calculations suggest that waters flows through BNNT of smaller diameter than CNT [4]. Due to a giant surface charge, BN is a good candidate for conversion of osmotic energy. A very recent experiment based on single BNNTs have shown that osmotic energy conversion reaches power density in the order of

sebastien.linas@univ-lyon1.fr

kW.m-2 [5] exceeding by several orders of magnitude the power density of other exchange membranes [1]. These extremely encouraging results concerning BN based membranes concern samples that are hardly producible at large scale. In order to benefit from the superior properties of BN while producing large-scale and high density membranes, demonstrate the use of a thin hexagonal boron nitride (h-BN) film patterned by focused ion beam (FIB) to etch nanochannels (Fig. a) [6]. FIB has been used to pattern the h-BN membrane with an arbitrary pattern (Fig. b) and to produce nano-channels arrays (20 to 100 nm in diameter) in a h-BN membrane specially designed for nanofluidic measurements that are currently ongoing.

References [1] [2] [3] [4] [5] [6]

Logan et al., Nature, 488 (2012) 313. Shannon et al., Nature, 452 (2008) 301. Church et al., PNAS, 81 (1984) 1991 Won et al., JACS, 129 (2007) 2748. Siria et al., Nature, 494 (2013) 455. Linas et al., RSC Adv., (2015) Accepted.

Figures Figure 1. (a) Fabrication process of h-BN membranes. h-BN is first grown on copper foils, the copper is then etched in an ammonium persulfate solution. The floating h-BN film is transferred onto a hollow silicon substrate and patterned by FIB. (b) ”LMI”, the logo of our laboratory patterned using FIB on a h-BN membrane. (c) SEM image of the device schematized in the inset: a hollow Si/SiN substrate covered by a h-BN membrane patterned by FIB. This sample has been designed for nanofluidic experiments.

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Templated Assembly of Nanoplasmonic Supercrystal Arrays

Luis M. Liz-Marzán1,2 llizmarzan@cicbiomagune.es

CIC biomaGUNE, Paseo de Miramón 182, 20009 Donostia – San Sebastian, Spain Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain

The integration of nanoparticle superstructures into daily life applications faces major challenges including the simplification of the self-assembly process, reduced cost and scalability. It is however often difficult to improve on one aspect without losing on another. Stamping and templated assembly have been used to create single- and multi-particle patterns, but these are typically limited to a small number of particles. We have recently developed a bench-top method that allows patterning a macroscopic substrate with gold nanoparticle supercrystals in a one-step process. The method allows parallelization and patterned substrates can be made with high throughput. The self-assembly of a variety of building blocks into crystalline superstructures takes place upon solvent evaporation and their precise placement over millimeter scale areas is induced by confinement of the colloidal suspension in micron sized cavities.

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We mainly focus on gold nanorods and demonstrate their hierarchical organization up to the device scale. The height of the formed nanorod supercrystals can be tuned by simply varying nanorod concentration, so that the topography of the substrate and the resulting optical properties can be readily modulated. The crystalline order of the nanorods results in homogeneous and high electric field enhancements over the assemblies, which is demonstrated by surface enhanced Raman scattering spectroscopy.

References [1] C. Hamon, S. Novikov, L. Scarabelli, L. BasabeDesmonts, L.M. Liz-Marzán, ACS Nano 2014, 8, 10694.

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Probing spectroscopic properties of BN and black phosphorous layers 1

L.Schué1,2, E. Gaufrès1,3, A. Favron3, F. Fossard1, A. Pierret1, J. Barjon2 ,F.Ducastelle1, R.Martel3 and A. Loiseau1

LEM, ONERA-CNRS, Châtillon, France GEMAC, Université Versailles St Quentin – CNRS, Versailles, France 3 RQMP and Département de chimie, Université de Montréal, Montréal, France 2

In this talk, we examine the interplay between structure and spectroscopic properties of both BN and Black Phosphorous (P(black)) mechanically exfoliated layers and how these properties can be further exploited in 2D layered heterostructures, beyond graphene. Spectroscopic properties were studied using cathode luminescence (CL) at 4K, Raman spectroscopy, HRTEM and Electron Energy Loss Spectroscopy (EELS) using a monochromated Libra 200 TEM-STEM at 80 kV. Hexagonal boron nitride (h-BN) is a wide band gap semiconductor (~ 6.5 eV), with sp2 hybridation, which meets a growing interest for deep UV LED and graphene and 2D materials engineering [1]. Knowing better the intrinsic properties of this material therefore highly desirable. H-BN displays original optical properties governed, in the energy range 5.5 – 6 eV, by strong excitonic effects, consisting of D and S lines [2]. Thanks to the imaging capability of the CL, emission, related to D lines, is proved to be due to structural defects identified by TEM as grain boundaries or folds. In defect free areas of thin layers, D lines completely vanish and S lines only are observed. S lines are therefore identified as the intrinsic luminescence of the material [2]. We will show how exfoliated layers could be prepared with no D band and that their S-emission dramatically changes when reducing the number of layers, providing with a signature of the 2D confinement [3]. Low-loss-EELS is an alternative approach to the nature of electronic excitations. One can indeed access to the onset of optical transitions and investigate their angular dependence. We will show that we can probe the whole Brillouin zone of BN layers appropriately cut in

TNT2015 toulouse (france)

a HPHT h-BN single crystal along definite crystallographic orientations and represent the Plasmon dispersion as a function of the q momentum [4]. P(black) thin layers have recently raisedinterest for their originalsemi-conducting properties,suchas tunable direct band gap and high carrier mobilities. Their study is however very challenging due to its fast degradation under ambient conditions. Thanks to Raman and core-loss EELS spectroscopy, we have investigated the chemistry of degradation and shown that this phenomenon is due to a thickness dependant photo-assisted oxidation reaction with absorbed oxygen in water. This oxidation is consistent with electron transfer model based on quantum confinement. On this basis we carried out appropriate manipulation procedures opening a route to first Raman TEM and Low-loss EELS measurements on pristine mono-, bi- and multi layers, which will be discussed [5].

References [1] C.R. Dean et al. Nature Nanotechnology 5 (2010) 722. [2] A. Pierret et al, Phys. Rev. B, 89 (2014) 035414. [3] L. Schué et al, submitted 2015. [4] F. Fossard et al, in preparation (2015). [5] A. Favron etal, Nature Materials, published on line 22 May 2015.

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Surface Conductive Graphenewrapped Micro-motors Exhibiting Enhanced Motion

Xing Ma1, Yongfei Zeng2, Yanli Zhao2 and Samuel Sanchez1,3,4 xingma@is.mpg.de

Max Planck Institute for Intelligent Systems Institution, Stuttgart, Germany Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 3 Institució Catalana de Recerca i EstudisAvancats (ICREA), Barcelona, Spain 4 Institut de Bioenginyeria de Catalunya (IBEC), Barcelona, Spain 2

Janus micro/nano-motors have attracted significant research interest recently, and we fabricated Janus micro/nano motors driven by both bio-catalytic and catalytic reactions [1]. However, rising argument on fundamental motion of catalytic Janus spherical motors requires in practice experimental support. Surface conductive Janus motors might be able to give answers to the question of neutral/inoic diffusiophoresis and electrophoresis. Thus, we delicately introduce conductive 2-D nanomaterial, reduced graphene oxide (RGO) [2], to fabricate surface conductive Janus spherical motors. Given the same H2O2 fuel concentration, the velocity of the new motors is enhanced by about 100 % comparing to Janus motors with insulating surface. The velocity increase is partially attributed to improved catalytic activity due to presence of RGO and surface roughness [3]. Meanwhile, the result infers possible existence of charge transfer through motor’s surface, which enhances inoic species diffusion and thus further increase motors’ velocity [4]. In addition to new fundamental findings, the presence of RGO

on the surface of micromotors opens many possibilities from biomedical to water remediation applications.

References [1] a) X. Ma and S. Sanchez, Chem. Commun., 51 (2015) 5467; b) X. Ma, K. Hahn and S. Sanchez. J. Am. Chem. Soc. 137 (2015) 4976–4979. [2] a) S. Sreejith, X. Ma, Y. Zhao, J. Am. Chem. Soc. 134 (2012) 17346; b) S. Yang, X. Feng, S. Ivanovici, K. Müllen, Angew. Chem., Int. Ed. 49 (2010) 8408. [3] U. Choudhury, Ll. Soler, J. Gibbs, S. Sanchez and P. Fischer. Chem. Commun. 51 (2015) 8660. [4] a) A. Brown, W. Poon, Soft Matter 10 (2014) 4016; b) S. Ebbens, D. A. Gregory, G. Dunderdale, J. R. Howse, Y. Ibrahim, T. B. Liverpool, R. Golestanian, Epl-Europhys. Lett. 2014, 106.

Figures

Figure 1. a) Schematic illustration of fabrication of Janus SiO2-Pt micromotors and reduced graphene oxide wrapped Janus SiO2@RGO-Pt micromotors, b) Velocity comparison and c) Mean-square-displacement plot of the two motors.

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Comparative study of nano-scale and macro-scale field-effect mobility in CVD graphene 1

Department of Micro- and Nanotechnology and Department of Photonics Engineering, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark 3 Graphenea S.A., Tolosa Hiribidea 76, 20018 Donostia-San SebastiĂĄn, Spain

As commercial applications of graphene based technologies start emerging, accurate and rapid electrical characterization of large-area CVD graphene is becoming increasingly important for monitoring graphene growth/transfer uniformity and reproducibility [1]. Terahertz spectroscopy has been touted as an excellent non-contact method for electrical characterization of graphene, making it useful for a range of commercial applications where it is important to identify the sheet conductance [2] and field-effect mobility [3]. THz spectroscopy probes these parameters on the scale of tens to hundreds of nanometres [2] whereas the conventional macroscopic van der Pauw technique probes the same parameters on much larger scale, e.g. 1 mm. In this study we evaluate the difference in field-effect mobility extracted with these two methods. We present measurements of large-area CVD graphene and are able to make direct comparisons between gated broadband THz measurements with gated van der Pauw measurements on the same devices. With concurrent Hall effect measurements this allows us to determine the carrier concentration independently from the typical capacitance/mobility calculation. This enables a systematic comparison between the nano-scale and macro-scale field-effect mobilities as well as the macro-scale Hall mobility due to our calibrated carrier concentration.

D. M. A. Mackenzie1, J. D. Buron1, P. R. Whelan1, B. S. Jessen1, A. Zurutuza2, A. Pesquera2, A. Centeno2, P. U. Jepsen3, P. BĂ¸ggild1, D. H. Petersen1 dmac@nanotech.dtu.dk

Figures

References [1] A. Zurutuza et. al., Nature nanotechnology, 9(10), 730-734. (2014). [2] J.D. Buron, et al., Nano Lett. 12, 5074 (2012). [3] J.D. Buron, et al., Sci. Rep. in review.

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Figure 1. Gated measurements performed on mm -sized areas of CVD graphene: a) using van der Pawl measurement technique with fixed gold electrodes. Inset: typical device with example of vdP circuit. b) using broadband transmission THz spectroscopy. Inset: schematic of terahertz setup showing gated measurements of graphene.

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Recent technology advancements in SPM based electrical probing at low temperatures

Markus Maier, JĂźrgen Koeble, JĂźrgen Chrost Markus.Maier@scientaomicron .com

Scienta Omicron GmbH, Limburger Str. 75, 65232 Taunusstein, Germany

A major challenge in the development of novel devices in nano- and molecular electronics is their interconnection with larger scaled electrical circuits. Local electrical probing by multiple probes with precision on the atomic scale can significantly improve efficiency in analyzing electrical properties of individual structures on the nano-scale without the need of a full electrical integration.

Figures

The LT NANOPROBE is a dedicated microscope stage that merges the requirements of a SEM navigated 4-probe STM and at the same time satisfies the needs for high performance SPM. Besides SEM/SPM probe fine navigation, the excellent STM/NC-AFM imaging performance with atomic resolution at T<5K,expands applications to tunneling spectroscopy and even the creation of atomically precise structures. We will present measurements that prove the performance level of the instrument, specifically the low thermal drift, which allows for sufficient measurement time on extremely small structures as well as QPlus AFM measurements, which become important if nanostructures are deposited on an insulating substrate for a better electrical decoupling. We will also show the newest technology improvements and challenges as well as application and scientific drivers for this type of scientific instrumentation.

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Exciton Dynamics in 2D Semiconductors Based on Transition Metal Dichalcogenides 1 2

UniversitĂŠ de Toulouse, INSA-CNRS-UPS, LPCNO, Toulouse, France Ioffe Physical-Technical Institute of the RAS, 194021 St. Petersburg, Russia

G. Wang1, L. Bouet1, D. Lagarde1, I. Gerber1, M. Glazov2, E. Ivchenko2, A. Balocchi1, T. Amand1, B. Urbaszek1 and X. Marie1

marie@insa-toulouse.fr

The spectacular progress in controlling the electronic properties of graphene has triggered research in alternative atomically thin twodimensional crystals. Monolayers (ML) of transition-metal dichalcogenides such as MoS2 have emerged as very promising nanostructures for optical and electronic applications.

conditions is mainly explained by the very short recombination time [3, 6].

We have investigated the optical and valley properties for both neutral and charged exciton in transition metal dichalcogenide monolayers: MoS2, MoSe2 and WSe2.

References

In WSe2 MLs, we have combined linear and nonlinear optical spectroscopy (one and two-photons PLE, Second Harmonic Generation spectroscopy) in order to evidence the neutral exciton excited states. The clear identification of exciton excited states combined with first principle calculations allows us to determine an exciton binding energy of the order of 600 meV. The deviation of the excited exciton spectrum from the standard Rydberg series will be discussed. Moreover we show that exciton valley coherence can be achieved following one or two-photons excitation [1].

Finally recent results on magnetophotoluminescence spectroscopy on MoSe2 and WSe2 in Faraday configuration up to 9 T will be presented [7].

[1] G. Wang et al, Phys. Rev. Lett. 114, 97403 (2015) [2] G. Wang et al, Phys. Rev. B 90, 075413 (2014) [3] D. Lagarde et al, Phys. Rev. Lett 112, 047401 (2014) [4] C.R. Zhu et al, Phys. Rev.B 90, 161302(R) (2014) [5] M. Glazov et al, Phys. Rev. B 89, 201302(R) (2014) [6] G. Sallen, Phys. Rev. B 86, 081301(R) (2012) [7] G. Wang et al, 2D Mater. 2, 34002 (2015).

The neutral and charged exciton dynamics have been measured by time-resolved photoluminescence and pump-probe Kerr rotation dynamics [2,3]. The neutral exciton valley depolarization is about 6 ps, a fast relaxation time resulting from the strong electronhole Coulomb exchange interaction in bright excitons [4]. Its temperature dependence is well explained by the developed theory, taking into account the longrange Coulomb exchange interaction [5]. In contrast the valley polarization decay time for the charged exciton is much longer (~1ns). The large neutral exciton valley polarization induced by polarized light measured in stationnary

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The mechanical action of the spin curl optical forces

Manuel I. Marqués1,2 , Juan José Sáenz2,3,4

manuel.marques@uam.es Departamento de Física de Materiales, Universidad Autónoma de Madrid, Spain Centro de Investigación en Física de la Materia Condensada (IFIMAC) and Instituto de Ciencia de Materiales “Nicolás Cabrera”, Universidad Autónoma de Madrid, Spain 3 Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Spain 4 Donostia International Physics Center (DIPC), Donostia-San Sebastian, Spain 2

The scattering force on dipolar particles, which is proportional to the imaginary part of the polarizability of the particle and to the phase gradients of the fields [1-3] is traditionally considered to be proportional only to the Poynting vector, but there is an additional contribution [4,5] proportional to the curl of the spin angular momentum of the light field [6]. The contribution to the scattering force given by the full Poynting vector plus this spin curl contribution is equivalent to consider only the so-called orbital component of the Poynting vector [7-9].The mechanical action of these spin forces is important, for example, in the focal volume of microscope objectives [10-12] and in evanescent fields [13,14]. In this work we explicitly show the importance of the non-conservative force coming from the curl of the spin density of the light field in stationary wave configurations [6,15] where it is possible to find arrangements with an effective value of the Poynting vector different from zero but no scattering force at all, and arrangements with a null value of the Poynting vector and an effective scattering force coming purely from the spin density of the light field. We also analyze the mechanical action of the spin curl force on the focal plane of particular, nonhomogeneous wave fronts, where the scattering force on a dipolar particle does not follow the Poynting vector [16]

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References [1] C. Cohen-Tannoudji et al., Atom-photon interactions Willey-Interscience, 1992. [2] A. Hemmerich and T. W. Hansch, Phys. Rev. Lett. 68 (1992) 1492. [3] Y. Roichman et al., Phys. Rev. Lett. 100 (2008) 013602. [4] J. R. Arias-Gonzalez, M. Nieto-Vesperinas, J. Opt. Soc. Am. A 20 (2003) 1201. [5] V. Wong and M. Ratner, Physical Review B 73 (2006) 075416. [6] S. Albaladejo, M. I. Marqués, M. Laroche, and J. J. Sáenz, Phys. Rev. Lett. 102 (2009) 113602. [7] D. B. Ruffner and D. G. Grier, Phys. Rev. Lett. 111 (2013) 059301. [8] M. I. Marqués and J. J. Sáenz, Phys. Rev. Lett. 111 (2013) 059302 [9] M. V. Berry, J. Opt. A: Pure Appl. Opt. 11 (2009) 094001. [10] T. Iglesias and J. J. Sáenz, Opt. Commun. 284 (2011) 2430. [11] Q. Zhan Opt. Express 20 (2012) 6058. [12] A. Bekshaev, K. Y.Bliokh, and M. Soskin, Journal of Optics 13 (2011),053001. [13] K. Y. Bliokh and F. Nori Phys. Rev. A 85 (2012) 061801(R). [14] A. Canaguier-Durand, A. Cuche, C. Genet, and T. W. Ebbesen, Phys. Rev. A 88 (2013), 033831. [15] M. I. Marqués and J. J. Sáenz Opt. Lett. 37 (2012) 2787. [16] M. I. Marqués Opt. Lett. 39 (2014) 5122.

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Stimuli responsive hybrid nanomaterials: applications in drug delivery and imaging

J.D. Marty1, C. Frangville1, N. Lauth-de Viguerie1, R. Haag2, D. R. Talham3 C. Mingotaud1 marty@chimie.ups-tlse.fr

Université de Toulouse; UPS/CNRS; IMRCP, F-31062, Toulouse Cedex 9, France Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany 3 Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, USA 2

Organic-inorganic nanoparticles are an appealing class of colloids to be used in nanopharmaceutics. Recently their great potential not only for imaging and diagnosis but also for clinical therapeutics has started to flourish. Adequately choosing the constituents leads to systems that can response to external stimuli (magnetic or electric field, light, temperature…) [1-4]. These stimuli responsive hybrid nanomaterials proved to be useful materials in nanomedecine to control the activity of nanovectors towards a specific application (diagnostic or therapeutic) [5].

homeostasis in neurodegenerative diseases, e.g., Alzheimer’s disease [4].

In the context of neurodegenerative diseases, e.g., Alzheimer’s disease, copper is a key biological cofactor. Exogenous supply of Cu to brain is one of the therapeutic approaches for addressing such deficien-cy symptoms. However, Cu needs to be transported into the central nervous system (CNS) and bypass the blood-brain-barrier (BBB), which remains an unsolved problem. Promising systems for this purpose are nanocarriers, which can bind Cu-ions selectively and release them specifically into the cellular environment in response to biochemical triggers, such as altered pH that is existing in the pathological tissues. Hyperbranched nanohybrids based on the use of pH responsive polymers were thus designed for the transport and triggered release of Copper ions in the context of Alzheimer disease. By designing new core-shell and core-multishells polymeric structures, we were able to get nanocarriers presenting a high binding affinity for copper ions and able to release these ions at low pH. We demonstrate that the exact architecture of the core-shell system is a paramount parameter to control the maximum loading, the strength of com-plexation and the release profile of copper into the solution. Their low toxicity may open a new way to balance the Cu-

References

TNT2015 toulouse (france)

Another example takes advantages of stimuli responsive polymers for the stabilization of GdPO4 nanoparticles obtained from microwaves synthesis with application as magnetic resonance imaging contrast agent. The critical effect of nanoparticle size, morphology, temperature, polymer structure and concentration on in vitro and in vivo relaxivity properties of the as-synthesized hybrids will be discussed.

[1] Beija, M., Marty, J.D., Destarac, M., Chem. Commun., 47 (2011), 2826. [2] Keilitz, J., Radowski, M., Marty, J.D., Haag, R., Gauffre, F., Mingotaud, C., Chem. Mater., 120 (2008), 2423. [3] Glaria, A.; Beija, M.; Bordes, R.; Destarac, M.; Marty, J.D., Chem. Mater., 24 (2013), 1868. [4] Nowag, S., Frangville, C., Achazi, K., Multhaup, G., Marty, J.-D., Mingotaud, C., Haag, R. J. Mater Chem B, 2 (2014), 3915. [5] Beija, M., Lauth-de Viguerie, N., Salvayre R., Marty, J.-D., Trends in biotechnology, 30 (2012), 485.

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Figures

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Effect of polymer surface adsorption on graphene nanoplatelets biocompatibility

Artur M. Pinto1,2, J. Agostinho Moreira3, Inês C. Gonçalves2, Fernão D. Magalhães1

arturp@fe.up.pt

LEPABE, Faculdade de Engenharia, Universidade do Porto, Porto, Portugal INEB, Universidade do Porto, Porto, Portugal 3 IFIMUP and IN – Institute of Nanoscience and Nanotechnology, Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal 2

Introduction: Several biomedical applications have been studied for graphene-based materials (GBMs), including biosensing/bioimaging, drug delivery, cancer photothermal therapy, regenerative medicine, and antibacterial materials. In view of the growing interest in using GBMs in this context, it is paramount to evaluate their biocompatibility. The present work studies a commercially available product, with reduced cost comparing with single layer graphene: graphene nanoplatelets (GNP). GNP has been reported to display good results as biopolymers fillers, improving mechanical and thermal performance, and biocompatibility, namely reducing platelets activation without increasing toxicity [1]. Covalent and non-covalent surface modification with polymers is a strategy to overcome possible toxicity of GBMs powders. Covalent functionalization often implies using toxic solvents as reaction medium, while the procedures for non-covalent surface modification are simple and easily up-scalable. This work aims to study the biocompatibility of GNP, as well as the effect of noncovalent surface modification with several biocompatible polymers. Materials and Methods: Graphene nanoplatelets C750 (GNP-C), were acquired from XG Sciences, having thickness <2 nm, length 1-2 μm, surface area 750 m2g-1. GNP-C were modified by surface adsorption with different polymers, namely: poly(vinyl alcohol) - PVA, hydroxyethyl cellulose HEC, poly(ethylene glycol), poly(vinyl pirrolidone), chondroitin sulfate potassium, glucosamine sulfate potassium and hyaluronic acid. Polymers and GNP-C (1:1 ratio) were dispersed in water performing sonication with a Hielsher UIP 1000 probe during 5 minutes. The dispersion was then centrifuged at 4000 rpm for 15 min and supernatant discarded, assuring removal of excess polymer. Scanning

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electron microscopy (SEM) was used to observe morphology. Dynamic Light Scattering (DLS), X-ray photoelectron spectroscopy (XPS), Raman Spectroscopy, and Thermogravimetric analysis (TGA) were used for chemical characterization and quantification of the mass of adsorbed polymers. Hemolysis and Resazurin assays were performed to evaluate GBMs biocompatibility with HFF-1 cells. Also, Live/Dead assay was made, in which dead cells were stained with propidium iodide (PI), live cells with calcein and the total number of cells with hoechst 33342, allowing calculation of cell death (%).Transmission electron microscopy (TEM) images were obtained to evaluate GNP/cell interactions. Reactive oxygen species (ROS) were quantified using the indicator CM-H2DCFH-DA. Results and discussion: All materials were characterized but here, results are presented only for GNP-C modified with PVA and HEC, since these materials unveiled the best non-hemolytic properties. SEM images reveal that GNP-C is constituted by individual particles with diameter around 2 μm and small wrinkled flakes (0.5 μm). GNP-C-PVA forms a film on platelets surface, while GNP-C-HEC is in the form of very small particles. DLS results show that surface adsorption of polymers increase GNP-C particle sizes, which has two populations around 0.5 and 2 μm, due to encapsulation of the platelets and induction of interplatelet interactions that lead to agglomeration. Particle size increase is higher for GNP-C-PVA (around 25 μm) than for GNP-C-HEC (around 8 μm). XPS, Raman and TGA confirm the presence of polymers at GNP-C surface, being of 21 % and 15%, respectively for GNP-C-PVA and HEC. Hemolysis for all GBMs, was below 1.7%, up to concentrations of 500 μg mL-1 at 3h. Live/Dead assay shows that cell death is low (<6%) for all materials in concentrations

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between 1-100 μg mL-1. For 20 and 50 μg mL-1, cell death is significantly lower (p < 0.05) for modified GNP-C-PVA, comparing to pristine GNP-C. For 50 μg mL-1, GNP-C increases ROS production by 4.4 fold comparing with negative control (PBS). For GNP-CPVA and HEC it also increases by 3.3 and 5.2 fold, respectively. These results are in agreement with those obtained in resazurin assay. TEM images show that GNP-C was almost completely exfoliated interacting with plasma membrane, being internalized without causing membrane damages, being found often in cytoplasm and in some cases interacting with mitochondria, which may induce ROS production. GNP-C-PVA was more agglomerated, presenting larger volume than GNP-C, being found more often outside plasma membrane than in cytoplasm. Internalized GNP-C-HEC particles presented smaller length (0.5 - 1.5 μm) than GNP-CPVA and GNP-C (0.5 - 3 μm), being often found spread in cytoplasm. GNP-C-HEC was also observed in contact in mitochondria. Conclusions: The biocompatibility of GNP modified by surface adsorption of polymers was evaluated in vitro. Hemolysis tended to decrease after adsorption of most polymers, however PVA and HEC presented the best results, and these materials were therefore characterized with more detail. Small sized GNP-C

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enters cells inducing ROS production, and therefore, toxicity. PVA encapsulation of GNP-C increased particle size, decreasing internalization and interaction with HFF-1 cells, therefore avoiding ROS production. HEC favoured internalization of small GNP-C particles, having the opposite effect. This work shows that GNP-C-PVA has potential to be used as coating or filler for medical devices, with the purpose of improving mechanical and/or thermal properties, while reducing acute toxicity, improving biointeractions and reducing infection probability. Also, smaller particles can be separated and used for drug delivery. GNP-C-HEC is more toxic, but its smaller particles present increased internalization, therefore potentially offering advantages in targeted delivery of toxic drugs or cancer photothermal ablation.

References [1] Pinto AM, Gonçalves IC, Magalhães FD, Colloids and Surf B Biointerfaces, 111 (2013) 188.

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Probing bandgap renormalization, excitonic effects, and interlayer coupling in 2D transition metal dichalcogenide semiconductors 1

M. M. Ugeda1,2, A. J. Bradley1, S.-F. Shi1, F. H. da Jornada1, Y. Zhang3,4, D. Y. Qiu1, W. Ruan1, S. Wickenburg1, A. Riss1, J. Lu1, S.-K. Mo3, Z. Hussain3, Z.-X. Shen4,5, F.Wang1,2, S. G. Louie1,2 and M. F. Crommie1,2

Department of Physics, University of California, Berkeley, CA 94720, USA Materials Sciences Division, Lawrence Berkeley National Lab., Berkeley, CA 94720, USA 3 Advanced Light Source, Lawrence Berkeley National Lab., Berkeley, CA 94720, USA 4 Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator mmugeda@berkeley.edu Laboratory, Menlo Park, CA 94025, USA 5 Geballe Laboratory for Advanced Materials, Stanford University, Stanford, USA 2

Atomically-thin transition metal dichalcogenide (TMD) semiconductors have generated great interest recently due to their remarkable physical properties. In particular, reduced screening in 2D has been predicted to result in dramatically enhanced Coulomb interactions that should cause giant bandgap renormalization and excitonic effects in single-layer TMD semiconductors. Here we present direct experimental observation of extraordinarily high exciton binding energy and band structure renormalization in a single-layer of semiconducting TMD[1]. We have determined the binding energy of correlated electron-hole excitations in monolayer MoSe2 grown via molecular beam epitaxy[2] on bilayer graphene (BLG) by using a combination of high-resolution scanning tunneling spectroscopy and photoluminescence spectroscopy. We have measured both the quasiparticle electronic bandgap and the optical transition energy of monolayer MoSe2/BLG, thus enabling us to obtain an exciton binding energy of 0.55 eV for this system, a value that is orders of magnitude larger than what is seen in conventional 3D semiconductors. In a more highly screened environment (on top of graphite), we find that single layers of MoSe2 show a strong 51% reduction in the exciton binding energy and an 11% reduction in the quasiparticle electronic gap, without significantly changing the optical gap. We have corroborated these experimental findings through ab-initio GW and Bethe-Salpeter equation calculations, which show that the large exciton binding energy arises from enhanced Coulomb interactions that lead to blue-shifting of the quasiparticle bandgap. We have also studied the

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role of interlayer coupling and layer-dependent carrier screening on the electronic structure[3] of few layer MoSe2. We find that the electronic quasiparticle bandgap decreases by nearly 1 eV when going from one layer to three. Our findings paint a clear picture of the evolution of the electronic wave function hybridization in the valleys of both the valence and conduction bands as the number of layers is changed. These results are of fundamental importance for the design and evaluation of roomtemperature electronic and optoelectronic nanodevices involving single layers of semiconducting TMDs as well as more complex layered heterostructures.

References [1] M. M. Ugeda, A. J. Bradley, et al., Nature Materials 13, 1091 (2014). [2] Y. Zhang, M. M. Ugeda, et al., Submitted (2015). [3] A. J. Bradley, M. M. Ugeda, et al., Nano Letters 15, 2594 (2015).

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Development of Large Scale Production of Self-Standing Graphene

Kazuo Muramatsu

Incubation Alliance,Inc., Japan

Incubation Alliance developed a technology for large scale, self-standing synthesis of graphene in high purity using the high-speed chemical vapor deposition CVD method without any catalyst. Our pure graphene raw material â&#x20AC;&#x2DC;Graphene Flowerâ&#x20AC;&#x2122; is already for mass production using conventional Hot Isostatical Pressing (HIP) equipment.

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Investigation of Metal Oxides Passivation for CVD Graphene 40GHz Photodetectors 1

GERAC Electromagnétisme, France Thales Research and Technology, France 3 Laboratoire de Physique des Interfaces et Couches Minces (LPICM), France 4 Laboratoire Pierre Aigrain, Département de Physique de l'ENS, France 5 Unité Mixte de Physique CNRS/Thales, France, and University of Paris-Sud, France 6 Graphenea S.A., Spain 2

Graphene has gained increasing attention over the last decade, due to its outstanding properties that make it an excellent candidate for advanced applications in future electronics and photonics [1]. In particular, the potential of graphene for highfrequency optoelectronic applications is currently being extensively explored because of its ultra-high carrier mobility and absorption from the far infrared to the ultraviolet [2,3]. However, this application requires the fabrication of highly stable devices. In this work, we aim at obtaining chemical vapor deposited (CVD) graphene based devices for radiofrequency (RF) optoelectronic applications. This target includes the necessity to develop a process that leads to a high control of graphene doping with long term stability. For that purpose, we investigated the impact of graphene passivation on the performances of stable graphene based photodetectors under ambient conditions and over months. More specifically, we report the evaluation of metal oxides layers, namely Al2O3 and HfO2, on key parameters of CVD graphene based devices, such as transistor characteristics or photodetectivity. Our passivation layers were deposited by atomic layer deposition (ALD) at the end of the fabrication process. The influence of an additional Al2O3 layer (obtained by ambient oxidation of thin Aluminum layer after graphene transfer) is also investigated to

Figure 1. : Transfer characteristics of a passivated graphene field effect transistor using HfO2 measured under ambient conditions after 4 weeks storage and subsequent annealing.

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S. Mzali1,2,3, A. Montanaro2,4, O. Bezencenet2, J-P Mazellier2, B. Dlubak5, M-B Martin5, B. Servet2, S. Xavier2, A. Centeno6, A. Zurutuza6, P. Seneor5, C-S Cojocaru3, P. Legagneux2

avoid parasitic graphene doping during the fabrication of photodetectors. Our RF photodetector is a coplanar waveguide structure on well-adapted substrate and with a thick metallization in order to make it compatible up to 40GHz and to limit RF-losses. Finally, we explore the link between graphene stable characteristics (Figure 1) and photoconductivity properties (Figure 2) in low and high frequency (up to 40GHz) domains. We show that electrical properties and photodetection measurements highlight the benefits of our optimized fabrication process. Besides, we demonstrate long term stable devices repeatedly tested for few months. This work was funded through the European projects Grafol and Graphene Flagship.

References [1] Novoselov K. S., et al., Nature, 490, 192−200 (2012). [2] Bonaccorso F., et al., Nature Photon., 4, 611– 622 (2010). [3] Geim A.K. & Noveselov K.S., Nat. Mater., 6, 183-191 (2007).

Figure 2. : Photoresponse of a coplanar waveguide integrating a graphene film at 5GHz

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Gold plated and thick shell quantum dots: two examples of colloidal quantum dots with much improved optical properties

M. Nasilowski, P. Spinicelli, B. Dubertret* benoit.dubertret@espci.fr

LPEM, ESPCI, 10 rue Vauquelin, 75005 Paris, France

The quest for the perfect quantum dot (QD) is a drive for both chemists and physicists. Since the landmark synthesis of colloidal semiconductor nanocrystals[1], many studies have tried to understand and limit QD emission blinking in time[2]. The most widely accepted explanation for the emission intensity flickering is the presence of an excess charge, in or in close proximity to the nanocrystal[3] that can recombine non radiatively with the exciton through Auger processes.. This results in heat, lower quantum yield, and fluctuation of the QD emission in time when observed at the single particle level. Recently, two routes have been proposed to decrease the efficiency of Auger recombination: composition gradient between the core and the shell[4] and thick shell QDs[5]. While this two routes have led to QDs with improved fluorescent properties, they both have their limitations: limited quantum yields for gradient QDs and strongly temperature dependent quantum yield for thick shell QDs. We present here two new generations of quantum dots with unmatched optical properties. The first one, a CdSe/CdS QD with a thick CdS shell and a gradient interface between the core and the shell, exhibit a quantum yield of 100% at room temperature, with a perfectly stable, non-blinking, fluorescence emission over long periods of time (hours). We measured a similar quantum yield for the monoexciton and for the biexciton, which shows that Auger recombinations are completely suppressed in these QDs. At high excitation powers, these QDs show multiexcitonic emission even at the single dot level, so that single QDs have excitation dependent light emission, another proof of the complete suppression of Auger recombination. The second one consists of a single quantum dot encapsulated in a silica shell coated with a

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continuous gold nanoshell.[6] It provides a system with a stable and Poissonian emission at room temperature that is preserved regardless of drastic changes in the local environment. This novel hybrid quantum dot/silica/gold structure behaves as a plasmonic resonator with a strong Purcell factor. The gold nanoshell also acts as a shield that protects the quantum dot fluorescence and enhances its resistance to high-power photoexcitation or high-energy electron beams. These two types of new QDs bring a rupture in the family of colloidal QDs in the sense that they are the first examples of 100% quantum yield QD at room temperature even at high excitation power, regardless of their charge state and with robust optical properties.

References [1] C. B. Murray, D. J. Norris, and M. G. Bawendi, J. Am. Chem. Soc., vol. 115, no. 19, pp. 8706– 8715, Sep. 1993. [2] M. Nirmal, B. O. Dabbousi, M. G. Bawendi, J. J. Macklin, J. K. Trautman, T. D. Harris, and L. E. Brus, Nature, vol. 383, no. 6603, pp. 802–804, Oct. 1996. [3] M. Kuno, D. P. Fromm, H. F. Hamann, A. Gallagher, and D. J. Nesbitt, J. Chem. Phys., vol. 115, no. 2, p. 1028, 2001. [4] G. E. Cragg and A. L. Efros, Nano Lett., vol. 10, no. 1, pp. 313–7, Jan. 2010. [5] C. Javaux, B. Mahler, B. Dubertret, A. Shabaev, A. V Rodina, A. L. Efros, D. R. Yakovlev, F. Liu, M. Bayer, G. Camps, L. Biadala, S. Buil, X. Quelin, and J.-P. Hermier, Nat. Nanotechnol., vol. 8, no. 3, pp. 206–12, Mar. 2013. [6] B. Ji, E. Giovanelli, B. Habert, P. Spinicelli, M. Nasilowski, X. Xu, N. Lequeux, J.-P. Hugonin, F. Marquier, J.-J. Greffet, and B. Dubertret, Nat Nano, vol. 10, no. 2, pp. 170–175, Feb. 2015.

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Wetting properties of partially suspended graphene monolayers 1

Nanosciences group, CEMES-CNRS, 29 rue Jeanne Marvig, 31055 Toulouse cedex 4, France 2 Brookhaven National Laboratory,Upton, NY, 11973, USA

Thierry Ondarçuhu1 Antonio Checco2, Marc Nuñez1, Vincent Thomas1, Erik Dujardin1, Atikur Rahman2 and Charles T. Black2 ondar@cemes.fr

Recently, the wetting properties of supported graphene monolayers has attracted a lot of attention due to the possible applications of graphene as a coating material A fundamental and yet unresolved issue is how the one-atom thick graphene layer influences the wettability of the underlying substrate by screening the liquid-substrate chemical, van der Waals and electrostatic interactions. Rather contradictory results have been reported, suggestive of either the wetting transparency [1] (no effect of graphene on the contact angle) or translucency [2, 3] of graphene (nearly constant contact angle on graphene, irrespective of the underlying substrate). A factor contributing to these controversial results is the adsorption of airborne contaminants that significantly alter the wetting properties of graphene [4].

temperature in reductive atmosphere to remove traces of ambient hydrocarbons. Water contact angle measurements were carried out on hydrophobic textures, where the droplet lies partially suspended on air, and on hydrophilic textures, where water was found to wick the texture resulting in graphene supported by both silicon and water. This experiment therefore allows to study the influence of the underlying substrate by allowing to change it gradually from air to silicon dioxide and water. Over this large range of experimental conditions, our results show a limited (< 30°) dependence of the contact angle on the chemical nature of the underlying substrate, suggesting a translucent behavior of graphene.

Here, we present an experimental study of the wetting properties of partially suspended graphene monolayers obtained by transferring graphene monolayers on recently developed nanostructured substrates. These surfaces, textured at the 50nm length scale, can be fabricated in a large range of morphologies including cones, cylindrical pillars, grooves and pits [5]. By transferring graphene on these substrates, we were able to gradually adjust the surface fraction of suspended graphene from a nearly free-standing graphene layer (on sharp cones the estimated graphene-substrate contact is estimated of the order of 5 %) to a fully supported one (on flat silica substrate) and thus assess quantitatively the role of the underlying substrate on the wettability of graphene. We used a new graphene transfer method that obviates the irreversible contamination associated to polymerassisted transfer. We demonstrate that this technique can be used successfully to deposit graphene monolayers large enough to perform macroscopic contact angle measurements on both (super)-hydrophilic and (super)-hydrophobic substrates. The samples were annealed at high

This study has been partially supported through the Laboratory of Excellence NEXT (grant n° ANR-10-LABX0037) in the framework of the “Programme des Investissements d’Avenir”. M.N. acknowledges the government of Andorra for a PhD fellowship. Research carried at Brookhaven National Laboratory is supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Contract No. DE-AC0298CH10886.

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Acknowledgments

References [1] Rafiee, J., Mi, X., Gullapalli, H., Thomas, A.V., Yavari, F., Shi, Y., Ajayan, P.M.,Koratkar, N.A., Nature Materials, 11 (2012) 217. [2] Raj, R., Maroo, S.C.,Wang, E.N., Nano Letters, 13 (2013) 1509. [3] Shih, C.-J., Wang, Q.H., Lin, S., Park, K.-C., Jin, Z., Strano, M.S.,Blankschtein, D., Physical Review Letters, 109 (2012) 176101. [4] Li, Z., Wang, Y., Kozbial, A., Shenoy, G., Zhou, F., McGinley, R., Ireland, P., Morganstein, B., Kunkel, A., Surwade, S.P., Li, L.,Liu, H., Nature Materials, 12 (2013) 925. [5] Checco, A., Rahman, A.,Black, C.T., Advanced Materials, 26 (2014) 886.

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Graphene Based composites for conventional and additive manufacturing

Amaya Ortega, Begoña Galindo aortega@aimplas.es

AIMPLAS, Parque Tecnológico Gustave Eiffel 4 Aptdo Correos 51, 46980, Paterna, Valencia, Spain

Graphene-based composites manufactured on a lab scale have been shown to exhibit impressive properties over unreinforced polymers. A small percentage of graphene within a polymer matrix can significantly improve its strength, stiffness and electrical conductivity, however the material remains prohibitively expensive for large-scale use as a composite reinforcement. Therefore, the concept for this project is to develop the knowledge-based processing methods required to up-scale the production of graphene and expanded graphite reinforced thermoplastic masterbatches and compounds and, ultimately, enable its industrial commercialisation in Europe. The work is focused on developing processes for large scale rapid production of graphene reinforced plastic intermediate materials, which can be integrated into current conventional and additive manufacturing processes. Injection moulding, extrusion blow moulding and film extrusion are all well-established moulding methods for producing parts at very high throughputs. Compounds and masterbatches are commonly used in these processes, and the graphene reinforced thermoplastic compounds and masterbatches will simply fit into the existing manufacturing chain, enabling the functionality of these materials to be applied to high volume components. Additive Manufacturing (AM) is a process of joining materials to make objects from 3D model data, usually layer upon layer, as opposed to subtractive manufacturing methodologies such as machining.

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The biggest advantage of additive manufacturing is the flexibility in the production due to a tool free process, which also reduces the costs and the time to market of new products. Due to the layered nature of the part generation, additive manufacturing can deliver unique materials, structures and properties. Graphene and expanded graphite based materials have been developed and optimise nanocomposite processing parameters - both for conventional processes such as injection moulding and film extrusion; and for additive manufacturing processes, including selective laser sintering and fused deposition modelling. The research leading to these results has received funding from the European Community's Seventh Framework Programme FP7/2007-2013 under grant agreement n° 285718.(Nanomaster project)

References [1] Chua Ck, Leong KF,Lim CS. Rapid Prototyping: Principles and applications.3rd Edition, World scientific. (2003) [2] B Galindo, S Gil Alcolea, J Gómez, A Navas, A Ortega Murguialday, M Pérez Fernandez and R C Puelles. Effect of the number of layers of graphene on the electrical properties of TPU polymers. IOP Conference Series: Materials Science and Engineering Volume 64 conference 1 (2014)

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Graphene and other 2d crystals for energy devices

Vittorio Pellegrini

Graphene Labs, Istituto Italiano di Tecnologia Genova, Italy

Energy conversion and storage are two of the grand challenges that our society is facing. New materials and processes [1] can improve the performance of existing devices or enable new ones that are also environmentally benign. In this talk we will start by reviewing recent progress on the application of graphene, related two-dimensional crystals, and hybrid systems for energy conversion and storage [2]. The versatility of graphene and related materials can lead to new power management solutions for portable and flexible devices, as well as integration in living environments. We will then focus on our recent developments of graphenebased ink battery that displays an estimated energy density of about 200 Whkg-1 and a stable operation for over 80 charge-discharge cycles [3]. These properties are linked to the graphene nanoflake anode displaying crystalline order and high uptake of lithium at the edges. We also discuss the role of the graphene nanoflake morphology on the mechanism of lithium uptake highlighting the impact of the number of graphene layers and nanoflake lateral sizes on irreversible/reversible capacities [4]. Our approach, compatible with any printing technologies, is cheap and scalable and opens up new opportunities for the development of high-capacity Li-ion batteries.

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References [1] F. Bonaccorso, et al., Production and processing of graphene and 2d crystals. Materials Today, 15, 564 (2012). [2] F. Bonaccorso, et. al., Graphene, 2d crystal and hybrid structures for energy conversion and storage. Science 347, 1246501 (2015). [3] J. Hassoun, et al. An advanced lithium-ion battery based on a graphene anode and a lithium iron phosphate cathode. Nano Lett. 14, 4901-4906 (2014). [4] H. Sun et al. in preparation

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Temperature Influence of Production of Single and Multilayer Graphene Oxide

Flavio Pendolino1, Nerina Armata2, Tiziana Masullo3, Angela Cuttitta3 flavio.pendolino@unipd.it

University of Padova, via Marzolo 9, 35131 Padova, Italy 2 University of Palermo, Viale delle Scienze, 90128 Palermo, Italy 3 Consiglio Nazionale delle Ricerche (IAMC-CNR), Italy

The discovery of the two-dimentional carbon material (graphene) by Geim and Novoselov [1] gathers the interest of research community in carbon allotropes as promising materials in a wide scenario of emerging technologies [2-4]. Recently, graphene oxide (single) and graphite oxide (multilayer), due to their properties, grow the curiosityâ&#x20AC;&#x2122;s researchers for their potential use in energy sustainable technologies, such as photovoltaic, solar heater [4-5]. Our investigation is focused on modulating the properties of oxidized carbon materials modifying the synthetic conditions (see Figures), in the view of applicability on nanoscale. By using a few-steps method [6], two forms of carbon oxides are generated, i.e. single or multilayer, which are function of the operating temperature. Even if apparently similar, these materials exhibit distinctive physical and chemical properties with a specific reactivity which affects the characteristic of possible future applications. Archived behaviours suggest a context where the properties needed for a material can be straightforward obtained by modifying the temperature. Moreover, the final oxidized products can be modified when another carbon allotrope

(e.g. single wall material) is used. All of these materials raise the prospect of an advantage owing to the feasibility of modulate/engineering the properties and the low cost and scale up production.

References [1] Novoselov KS, Geim AK, Morozov SV, et al. Science, 306 (2004) 666. [2] Compton OC, Nguyen ST, Small, 6 (2010) 711. [3] Su C, Loh KP, Acc. Chem. Res., 46 (2013) 2275. [4] Raccichini R, Varzi A, Passerini S, Scrosati B, Nat. Mater., 14 (2015) 271. [5] Xu C, Xu B, Gu Y, et al., Energy Environ. Sci., 6 (2013) 1388. [6] Pendolino F, Parisini E, LoRusso S, J. Phys. Chem. C, 118 (2014) 28162.

Figures

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Additive Free, Single Layer Graphene in Water & Few Graphene layers from Food Waste

Alain Pénicaud, George Bepete, Carlos Drummond, Eric Anglaret, Katerina Kampioti and Kai Huang

Centre de recherché Paul Pascal – CNRS, Université de Bordeaux, France

& Laboratoire Charles Coulomb, Université de Montpellier – CNRS, France (i) Full exfoliation of graphite to form thermodynamically stable, negatively charged, graphene (graphenide) flakes in solution can be achieved by dissolution of graphite intercalation compounds (GICs) in low boiling point aprotic organic solvents under inert atmosphere [1]. We now report that, under certain conditions, graphenide can be transferred to water as single layer graphene. The organic solvent can then be evaporated to remain with an aqueous graphene suspension of ca 0.1 mg/ml concentration under ambient atmosphere. The Raman spectra (2.33 eV laser) collected in situ on such dispersions show bands at 1343, 1586, 1620 and 2681 cm-1 corresponding to the D, G, D’ and 2D bands of graphene respectively. The 2D band at 2681 cm-1 is well fitted with a sharp lorentzian line (∼29 cm-1) which is a hallmark of single layer grapheme [2]. We have thus succeeded in preparing air stable, bulk suspensions of single layer graphene in water [3].

References [1] A. Catheline et al. Soft Matter, 12, 7882, (2012) [2] Y.Y. Wang et al. J. Phys. Chem. C., 112(29), 10637, (2008). [3] G. Bepete, C. Drummond, A. Pénicaud, European patent, June 12, 2014, EP14172164 [4] European community funded FP7 project PLASCARB. http://www.plascarb.eu/

(ii) Food waste can be transformed into graphitic carbon and renewable hydrogen using an innovative low energy microwave plasma process at industrial scale. The obtained nanocarbon is obtained through energy efficient transformation of methane resulting from decomposition of food waste [4]. After purification, well defined, high concentration aqueous dispersions of nanocarbons are obtained and characterized. They contain calibrated multilayer graphene particles. Conducting inks and films can be prepared from these dispersions.

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A. Pérez-Márquez1, J. Maudes1, N. Murillo1, N. Arconada2, AM. Goitandia2, M. Blanco2

Chemical decontamination of polluted water 1

TECNALIA, Pº Mikeletegi, 2, Parque Tecnológico, Donostia-San Sebastián, Spain IK4-TEKNIKER Iñaki Goenaga 5, Polo Tecnológico, Eibar, Spain

Fresh water is a scarce good because is the six percent of the total Earth water. Guarantee the access to drinking water, under full potential scenarios, is a necessity in case of manmade or accidental events and technologies for the decontamination is need. Authors demonstrated the benefit of electrospun nanofibres membranes in water decontamination in case of chemical pollution and their excellent adsorption properties to reduce pollutant concentration due to their high large-to-volume ratio. Electrospinning is a simple, low-cost and versatile method for fabricating continuous fibers with diameters ranging from micrometers to few nanometers. Poly-acrilonitrile (PAN) and Polyamide-6 (PA6) materials have been selected among others[1] water treatment materials because of their mechanical properties and their extensive use in commercial microporous water membranes. Several author combine the commercial membranes with electrospun layers, in the present work, authors manufacture electrospun thick layer membranes with substrate with a high mechanical performance and easy to handle for their direct use in the decontamination process. Material manufacturing conditions has been optimized to achieve homogeneous diameter distribution in nanofibers membranes and their

ana.perez@tecnalia.com

diameter and morphology were observed by SEM, figure 1. The chemical decontamination test was been carried out by an organic pollutant simulant, methyl orange (MO) dye. MO adsorption in both nanofibers membranes was investigated using a UV-vis/NI (Perkin Elmer Lambda 950) in the wavelength range 380nm - 1000nm. Initial MO concentration in water was 3mg/l. As shown in figure 2, after 90 minutes more than 60% and 70% of MO was eliminated of the initial solution from PA6 and PAN respectively. The pronounced pollutant concentration decrease is significant in comparison with previous studies [2]. The experimental evidences allow us to conclude than electrospun nanofibres membranes are a really fast and efficient solution for polluted water decontamination based on adsorption phenomena.

References [1] L. Yurramendi, J. L. Aldana, A. Page, A. P. Márquez, N. Murillo and F. Seco. IWA Nano and Water 2011, Ascona, Switzerland, 15th. [2] Chureerat Prahsarn, Wattana Klinsukhon, Nanjaporn Roungpaisan. Materials Letters 65, 15-16 (2011) p 2498.

Figures

Figure 1. SEM micrographs: (a) PA6 nanofibers and b) PAN nanofibers membranes

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Figure 2. Degradation of MO dye by adsorption in PAN and PA6 nanofibres membranes.

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INL Therapeutics: innovative systems for the induction of immunotolerance and selective cell death 1 2

Liliana Pires1, Begoña Espiña1, Vânia Vilas-Boas1,2, Félix Carvalho2, Manuel Bañobre1 and Inês Pinto1

International Iberian Nanotechnology Laboratory (INL), Portugal Faculty of Pharmacy, University of Porto, Portugal

The advent of nanotechnology has opened new avenues for creating alternative and innovative approaches to be applied in clinical practice. Within the general framework of INL research in nanomedicine we investigate and develop nano and micro-based systems for the treatment of neurogenerative diseases, such as multiple sclerosis, and cancer. Multiple sclerosis is a neurodegenerative disease in which degeneration is triggered by the abnormal infiltration in the central nervous system of immune cells which shown an aberrant behaviour recognizing and degrading myelin. The use of tolerogenic vaccines is currently under investigation by the administration of specific peptides that are expected to be able to restore immune homeostasis, and consequently stop the aberrant degradation of myelin and neurodegeneration.

selective cell death. Magnetic hyperthermia (MHT) has emerged in recent years as an experimental anticancer strategy that may be used either alone or as a sensitizing strategy. It exploits the local heat generated by magnetic nanoparticles (MNPs) in an external alternating magnetic field. MNPs functionalized with specific antibodies against cancer cells are currently being investigated, in order to induce a localized heating of cancer cells. The efficacy of these nanoparticles in hyperthermia cancer therapy is tested at INL using in vitro models.

A comparative study revealed that vaccine application through transdermal microneedles can provide more effective immunization than subcutaneous injection, allowing significant antigen sparing. Moreover, these micro-structures hold the promise of allowing injection without pain, reducing the biohazardous waste and avoiding the need for specialized administration. Microneedles patches have been developed at INL for the transdermal delivery of drugs or peptides. As the dermis is a skin layer highly rich in immune cells, such as Langerhans cells, known to be responsible for inducing antigenspecific tolerance, we are interested on the development and application of these devices for the delivery of tolerogenic vaccines under the scope of multiple sclerosis. The development of anti-cancer therapies at INL is based on the use of targeted nanoparticles able to induce magnetic hyperthermia ultimately leading to

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A fully tunable Klein tunneling contact junction in graphene

B. Plaçais , Q. Wilmart, M. Boukhicha, A. Inhofer, M. Rosticher, P. Morfin, G.Fève and J.M. Berroir

Laboratoire Pierre Aigrain, Physics Department of the Ecole Normale Supérieure-PSL Research University, CNRS, Université Pierre et Marie Curie-Sorbonne Universités, Université Paris Diderot-Sorbonne Paris Cité, 24 rue Lhomond, 75231 Paris Cedex 05, France

Boron nitride supported or encapsulated graphene exhibit a large mobility with a ballistic length limited by acoustic phonons to at room temperature. It opens the way for a ballistic graphene electronics including standard Field effect transistors but also new architectures exploiting geometrical Dirac Fermion optics [1]. The main limitation to the performance of ballistic devices becomes the contact resistance, an issue which has been mostly addressed empirically. A graphene contact is a composite element made of two intrinsic contributions: the metal-graphene tunnel resistance and the contact junction resistance. The latter is due to the discontinuity between metallic doping in the contacted area and field-effect doping in the channel. The junction transparency and resistance depend on the junction length and the doping on both sides. Metallic doping itself stems from the work function imbalance between graphene and metal; the resulting electronic transfer is partially screened by the metal itself depending on the thickness of the double charge double layer at the metal-graphene interface [2].

In this work [3] we address directly the tunability of a contact junction using independent local back gates for the channel and the contacts. With 30-nm inter-gate gaps and h-BN gate insulator, we realize high-transparency and fully tunable contact junctions. Our device demonstrates contact doping reversal and active contact doping control up to GHz frequencies. This finding opens new functionalities in graphene electronics and optoelectronics. As an example we demonstrate the gain switching capability of our bi-gate device.

References [1] Q. Wilmart, S. Berrada, D. Torrin, V. Hung Nguyen, G. Fève, J-M. Berroir, P. Dollfus and B. Placais, 2D Materials 1, 011006 (2014). [2] G. Giovannetti, et al. , Phys. Rev. Lett. 101, 026803 (2008) [3] Q. Wilmart, M. Boukhicha, A. Inhofer, M. Rosticher, P. Morfin, N. Garroum, G. Fève, JM. Berroir, and B. Plaçais, submitted.

Figures

Figure 1. Graphene device with local and independent channel and contact gating

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TNT2015 toulouse (france)

Development of Aluminum Matrix Composites with Non-agglomerated Nanodiamond Reinforcements

Vladimir A. Popov

popov58@inbox.ru

National University of Science and Technology “MISIS”, Moscow, Russia

Agglomeration of nanodiamond particles is the main reason for their restricted industrial application. Mechanical alloying during production allows agglomerates splitting [1-3] and even distribution of non-agglomerated nanodiamond particles in the metal matrix, including the one made of aluminum alloys. But as a result of aluminum and nanodiamond mixture processing in a planetary mill for more than 8 hours, aluminum carbide can be formed (Fig.1). To avoid this, shorter processing time is required that is impossible under some circumstances. It was suggested that the main agglomerates splitting operation should be performed during copper or zinc matrix composite production (in the event that these metals are included into the required alloy), followed by processing with aluminum. In this case the period of processing a composite containing aluminum is reduced 5-7 times. Research has showed that intermediate production of a copper or zinc matrix composites allows complete splitting of nanodiamond agglomerates and their even distribution in the matrix (Fig.2). Further 100-120 minute joint processing with

aluminum powder allows obtaining even distribution of non-agglomerated nanodiamond particles within an aluminum alloy. The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under the EFEVE project, grant agreement 314582. The author is grateful to A.S.Prosviryakov, T.B. Sagalova and I.M.Karnaukh for assistance in investigation.

References [1] V. Popov, D. Többens, A. Prosviryakov. Physica Status Solidi A, 2014, 211, pp 2353–2358. [2] V.A.Popov, B.B.Chernov, A.S.Prosviryakov, V.V.Cheverikin, I.I.Khodos, J.Biskupek, U.Kaiser. Journal Alloys Compd. 2014, 615 (Supplement 1), S433-S436. [3] V.A.Popov, B.B.Chernov, A.M.Nugmanov, G.P.Schetinina. Fullerenes, Nanotubes and Carbon Nanostructures. 2012, 20 (4-7), pp 455458.

Figures

Figure 1. X-ray diffraction patterns from composite “Aluminum + nanodiamonds” after 8h treatment in planetary mill: vertical lines mark aluminum carbide peaks

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Figure 2. Granule surface of composite “Copper + nanodiamonds” after 4h treatment in planetary mill: arrows mark non-agglomerated nanodiamond particles

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The Quest for Charge Transport in single Adsorbed Long DNA-Based Molecules

Danny Porath

danny.porath@mail.huji.ac.il

Institute of Chemistry and Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Israel

References [1]

[2]

[3]

DNA and DNA-based polymers have been at the focus of molecular electronics owing to their programmable structural versatility. The variability in the measured molecules and experimental setups, caused largely by the contact problem, has produced a wide range of partial or seemingly contradictory results, highlighting the challenge to transport significant current through individual DNA-based molecules. A well-controlled experiment that would provide clear insight into the charge transport mechanism through a single long molecule deposited on a hard substrate has never been accomplished. In this lecture I will report on detailed and reproducible charge transport in G4-DNA, adsorbed on a mica substrate. Using a novel benchmark process for testing molecular conductance in single polymer wires, we observed currents of tens to over 100 pA in many G4-DNA molecules over distances ranging from tens to over 100 nm, compatible with a long-range thermal hopping between multi-tetrad segments. With this report, we answer a long-standing question about the ability of individual polymers to transport significant current over long distances when adsorbed a hard substrate, and its mechanism. These results may re-ignite the interest in DNAbased wires and devices towards a practical implementation of these wires in programmable circuits.

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[4]

[5]

[6]

[7]

[8]

[9] [10]

[11]

[12]

[13]

[14]

"Direct measurement of electrical transport through DNA molecules", Danny Porath, Alexey Bezryadin,Simon de Vries and Cees Dekker, Nature 403, 635 (2000). Cited 1281 times "Charge Transport in DNA-based Devices", Danny Porath, Rosa Di Felice and Gianaurelio Cuniberti, Topics in Current Chemistry Vol. 237, pp. 183-228 Ed. Gary Shuster. Springer Verlag, 2004. Cited 191 times “Direct Measurement of Electrical Transport Through Single DNA Molecules of Complex Sequence”, Hezy Cohen, Claude Nogues, Ron Naaman and Danny Porath, PNAS 102, 11589 (2005). Cited 190 times “Long Monomolecular G4-DNA Nanowires”, Alexander Kotlyar, Nataly Borovok, Tatiana Molotsky, Hezy Cohen, Errez Shapir and Danny Porath, Advanced Materials 17, 1901 (2005). Cited 69 times “Electrical characterization of self-assembled single- and double-stranded DNA monolayers using conductive AFM”, Hezy Cohen et al., Faraday Discussions 131, 367 (2006). Cited 42 times “High-Resolution STM Imaging of Novel Poly(G)-Poly(C)DNA Molecules”, Errez Shapir, Hezy Cohen, Natalia Borovok, Alexander B. Kotlyar and Danny Porath, J. Phys. Chem. B 110, 4430 (2006). Cited 22 times "Polarizability of G4-DNA Observed by Electrostatic Force Microscopy Measurements", Hezy Cohen et al., Nano Letters 7(4), 981 (2007). Cited 55 times “Electronic structure of single DNA molecules resolved by transverse scanning tunneling spectroscopy”, Errez Shapir et al., Nature Materials 7, 68 (2008). Cited 84 times “A DNA sequence scanned”, Danny Porath, Nature Nanotechnology 4, 476 (2009). “The Electronic Structure of G4-DNA by Scanning Tunneling Spectroscopy”, Errez Shapir, et.al., J. Phys. Chem. C 114, 22079 (2010). “Energy gap reduction in DNA by complexation with metal ions”, Errez Shapir, G. Brancolini, Tatiana Molotsky, Alexander B. Kotlyar, Rosa Di Felice, and Danny Porath, Advanced Maerials 23, 4290 (2011). "Quasi 3D imaging of DNA-gold nanoparticle tetrahedral structures", Avigail Stern, Dvir Rotem, Inna Popov and Danny Porath, J. Phys. Cond. Mat. 24, 164203 (2012). "Comparative electrostatic force microscopy of tetra- and intra-molecular G4-DNA", Gideon I. Livshits, Jamal Ghabboun, Natalia Borovok, Alexander B. Kotlyar, Danny Porath, Advanced materials 26, 4981 (2014). "Long-range charge transport in single G4-DNA molecules", Gideon I. Livshits et. al., Nature Nanotechnology 9, 1040 (2014)

TNT2015 toulouse (france)

Synchrotron X-ray Scanning Tunneling Microscopy: Elemental Fingerprinting of Materials with Sensitivity at the Atomic Limit

Volker Rose, Nozomi Shirato, Marvin Cummings, Heath Kersell, Hao Chang, Daniel Rosenmann, Dean Miller, SawWai Hla vrose@anl.gov

Advanced Photon Source & Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, USA

The direct observation of the chemical composition and magnetic properties of nanoscale materials with high spatial resolution has been a longstanding goal. Scanning tunneling microscopy (STM) provides atomic resolution but fails to provide chemical sensitivity in complex situations. X-rays, however, provide that chemical sensitivity. In this talk we will discuss the development of a novel high-resolution technique, also known as synchrotron x-ray scanning tunneling microscopy (SX-STM). It combines the sub-nanometer spatial resolution of STM with the chemical, electronic, and magnetic sensitivity of synchrotron x-rays [1]. By using synchrotron x-rays as a probe and a nanofabricated smart tip of a tunneling microscope as a detector, we have recently achieved elemental fingerprinting of individual nickel clusters on a Cu(111) surface at 2 nm lateral resolution, and at the ultimate single-atomic height sensitivity (Fig.1.) [3]. Moreover, by varying the photon energy, we have succeeded to locally measure photoionization cross sections of just a single Ni nanocluster, which opens new exciting opportunities for chemical imaging of nanoscale materials.

Science, Office of Basic Energy Sciences, under contract DEAC02---06CH11357.

References [1] V. Rose, J.W. Freeland, S.K. Streiffer, “New Capabilities at the Interface of X-rays and Scanning Tunneling Microscopy”, in Scanning Probe Microscopy of Functional Materials: Nanoscale Imaging and Spectroscopy, S.V. Kalinin, A. Gruverman, (Eds.), Springer, New York (2011), pg 405-432. [2] M.L. Cummings, T.Y. Chien, C. Preissner, V. Madhavan, D. Diesing, M. Bode, J.W. Freeland, and V. Rose, Ultramicroscopy 112, 22-31 (2012). [3] Nozomi Shirato, Marvin Cummings, Heath Kersell, Yang Li, Benjamin Stripe, Daniel Rosenmann, Saw-Wai Hla, and Volker Rose, “Elemental Fingerprinting of Materials with Sensitivity at the Atomic Limit”, Nano Letters 14, 6499-6504 (2014).

Figures

The availability of direct chemical contrast in STM at the ultimate atomic limit is expected to find applications in nanoscience, material science, and chemistry. The author acknowledges generous funding by the Office of Science Early Career Research Program through the Division of Scientific User Facilities, Office of Basic Energy Sciences of the U.S. Department of Energy through Grant SC70705. Work at the Advanced Photon Source, the Center for Nanoscale Materials, and the Electron Microscopy Center was supported by the U.S. Department of Energy, Office of

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Figure 1. Synchrotron x-ray scanning tunneling microscopy (SX-STM) combines the high spatial resolution of STM with the chemical sensitivity of synchrotron x-rays [3].

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Multifunctional materials for electronics and photonics

Federico Rosei

Centre for Energy, Materials and Telecommunications, INRS, 1650 Boul. Lionel Boulet, J3X 1S2 Varennes (QC), Canada

The bottom–up approach is considered a potential alternative for low cost manufacturing of nanostructured materials [1]. It is based on the concept of self–assembly of nanostructures on a substrate, and is emerging as an alternative paradigm for traditional top down fabrication used in the semiconductor industry. We demonstrate various strategies to control nanostructure assembly (both organic and inorganic) at the nanoscale. We study, in particular, multifunctional materials, namely materials that exhibit more than one functionality, and structure/property relationships in such systems, including for example: (i) control of size and luminescence properties of semiconductor nanostructures, synthesized by reactive laser ablation [2]; (ii) we developed new experimental tools and comparison with simulations are presented to gain atomic scale insight into the surface processes that govern nucleation, growth and assembly [3-7]; (iii) we devised new strategies for synthesizing multifunctional nanoscale materials to be used for electronics and photovoltaics [8-26].

[8] [9]

[10] [11] [12] [13]

[14] [15] [16] [17] [18] [19]

References [1] [2]

[3] [4] [5] [6] [7]

F. Rosei, J. Phys. Cond. Matt. 16, S1373 (2004) D. Riabinina, C. Durand, J. Margot, M. Chaker, G.A. Botton, F. Rosei, Phys. Rev. B 74, 075334 (2006) K. Dunn, J. Derr, T. Johnston, M. Chaker, F. Rosei, Phys. Rev. B 80, 035330 (2009) F. Ratto et al., Small 2, 401 (2006) F. Ratto et al., Phys. Rev. Lett. 96, 096193 (2006) F. Ratto, S. Heun, O. Moutanabbir, F. Rosei, Nanotechnology 19, 265703 (2008) F. Ratto, T.W. Johnston, S. Heun, F. Rosei, Surf. Sci., 602, 249 (2008)

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[20] [21] [22] [23] [24] [25]

F. Ratto, F. Rosei, Mater. Sci. Eng. R 70, 243 (2010) O. Moutanabbir, F. Ratto, S. Heun, K. Scheerschmidt, A. Locatelli, F. Rosei, Phys. Rev. B 85, 201416 (2012) C. Yan et al., Adv. Mater. 22, 1741 (2010) C. Yan et al., J. Am. Chem. Soc. 132, 8868 (2010) R. Nechache et al., Adv. Mater. 23, 1724– 1729 (2011) R. Nechache, C. Harnagea, S. Licoccia, E. Traversa, A. Ruediger, A. Pignolet, F. Rosei, Appl. Phys. Lett. 98, 202902 (2011) B. Aïssa, R. Nechache, D. Therriault, F. Rosei, M. Nedil, Appl. Phys. Lett. 99, 183505 (2011) G. Chen et al., D. Ma, Chem. Commun. 47, 6308 (2011) G. Chen, S. Desinan, R. Rosei, F. Rosei, D. Ma, Chem. Comm. 48, 8009–8011 (2012) G. Chen, F. Rosei, D. Ma, Adv. Func. Mater. 22, 3914–3920 (2012) R. Nechache, C. Harnagea, F. Rosei, Nanoscale 4, 5588–5592 (2012) S. Li et al., Appl. Phys. Lett. 101, 192903 (2012) J. Toster et al., Nanoscale 5, 873–876 (2013) T. Dembele et al., J. Power Sources 233, 93– 97 (2013) S. Li et al., Chem. Comm. 49, 5856–5858 (2013) T. Dembele et al., J. Phys. Chem. C 117, 14510–14517 (2013) S. Li et al., J. Am. Cer. Soc. 96, 3155 (2013). R. Nechache et al., Nature Photonics 9, 61 (2015); S. Li et al., Small in press (2015).

TNT2015 toulouse (france)

Nano-bots as future trends in nano-bio-medicine

Samuel Sánchez sanchez@is.mpg.de

Max Planck for Intelligent Systems, Stuttgart, Germany, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain Institut Català de Recerca i Estudis Avancats (ICREA), Barcelona, Spain

Engineering tiny nano-bots that actively and directly transport drugs to specific locations is envisioned to be part of future nano-medicine. Over the last few years, there has been increasing interest in the use of chemistry to propel tiny machines in a similar way that nature uses biochemistry to power biological motors. Selfpowered micro-nano-bots are can be fabricated from multiple materials and by various methods, and have presented various applications in robotics, biosensing, nanomedicine, microfluidics, and environmental field [1].

[5] Khalil, App. Phys. Lett. 103, 172404 (2013) [6] S. Sanchez et al, J. Am. Chem. Soc., 133, 4860 (2011); Soler et al. LabChip 13, 4299 (2013) [7] Solovev A.A. et al, Angew. Chem. Int. Ed., 50, 10875. (2011); [8] Baraban, L. et al., Angew. Chem. Int. Ed., 52, 5552. (2013). [9] Soler, Ll. et al., ACS Nano, 7, 9611 (2013); Gao, W., Wang, J., ACS Nano, 8, 3170 (2014); Soler, L. Sanchez, S. Nanoscale, 6, 7175 (2014)

Figures Here, I will present our recent developments in this fascinating field. We fabricate nano-bots from mesoporous silica nanoparticles (Fig.1), microspheres up to rolled-up microtubular engines. Our types of hybrid Micro-bio-bots combine the best from the two worlds, biology and artificial nanomaterials providing remote control with biocompatible fuels. Nanomotors demonstrated the transport of drugs [2] micro-objects [3] and cells [4] with wireless magnetic guidance [5], temperature [6], and light [7]. Furthermore, they can act collectively reacting to external stimuli like chemotactic behaviour [8] and are capable of cleaning polluted water [9].

References [1] S. Sanchez, Ll. Soler and J. Katuri. Angew.Chem.Int.Edit. 54,1414-1444 (2015) [2] X. Ma, K. Hahn and S. Sanchez. J. Am. Chem.Soc. 137 (15), 4976–4979 (2015) [3] A. A. Solovev et al, Adv. Funct. Mater., 20, 2430 (2010); Solovev A. A. et al., ACS Nano, 6, 1751. (2012) [4] S. Sanchez et al, Chem. Commun., 47, 698. (2011)

TNT2015 toulouse (france)

Figure 1. Mesoporous Silica Janus Nanobots containing Pt on one side of the particle catalytically decompose H2O2 fuel and self-propell in solutions. Adapted from reference 2.

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Magnetic polymer micelles and nanovesicles for selective cytotoxicity by magnetic hyperthermia and magnetic field-triggered drug release

Olivier Sandre

olivier.sandre@enscbp.fr

Laboratoire de Chimie des Polymères Organiques (LCPO), UMR 5629 CNRS Université de Bordeaux / Bordeaux INP, ENSCBP, 16 avenue Pey Berland, F33607 Pessac, France

Many decades ago, clinicians proposed to destroy cancer cells by their heating with magnetic nanoparticles submitted to radiofrequency alternating magnetic fields (AMF). Since 2011, magnetic fluid hyperthermia is authorized as a complementary therapy of high grade brain cancer in synergy with radiotherapy. However, this utilization of AMF to achieve brain tumor necrosis necessitates stereotaxic injection of a high concentration of magnetic nanoparticles directly into the tumor, as developed at Charité Hospital in Berlin by the MagForce company, and the gain in patient lifetime is only moderate (a few months). In general, translation from laboratory to clinics of in vitro or in vivo magnetic hyperthermia experimental results is not straightforward due to the difficulty to concentrate magnetic nanoparticles at a localized spot inside a living organism, particularly in human. Therefore many teams work on other ways to use AMF to destroy cancer cells, at much lower iron oxide concentrations not allowing that temperature rises up macroscopically. One strategy named “magneto-chemotherapy” makes use of thermo-sensitive drug nanocarriers, by releasing a chemo-toxic drug in the vicinity of cancer cells by “local” (nanometer scale) heating in the vicinity of thermo-sensitive vectors encapsulating the drug. Magnetic thermo-sensitive copolymer nanovesicles loaded with the anticancer drug doxorubicin illustrate this method as demonstrated in vitro on HeLa cells [1]. A series of works recent highlighted the experimental finding that a significant cytotoxicity can also be induced by AMF application without any added drug or macroscopic temperature rise, introducing the concept of “cold hyperthermia”, or “intralysosomal hyperthermia”, since the most often

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cited mechanism would be the release of reactive oxygen species (ROS) in the cytoplasm provoked by a permeability increase of internal cellular membranes (endosomes) [2-6]. The second part of the talk will present our recent results of in vitro AMF-induced cytotoxicity, showing dose-responses on two cell lines (L929 murine fibroblasts and U87 human glioma cells) both with field application time and concentration of magnetic polyion complexation micelles made of arborescent copolymer core and a hydrophilic shell to insure colloidal stability in cell culture media [7].

References [1] H. Oliveira, E. Pérez-Andrés, J. Thevenot, O. Sandre, E. Berra, and S. Lecommandoux, Magnetic field triggered drug release from polymersomes for cancer therapeutics. Journal of Controlled Release 2013, 169 (3), 165-170. [2] L. Asin, G. F. Goya, A. Tres, M. R. Ibarra, Induced cell toxicity originates dendritic cell death following magnetic hyperthermia treatment. Cell Death & Disease 2013, 4 (4), e596. [3] R. Di Corato, A. Espinosa, L. Lartigue, M. Tharaud, S. Chat, T. Pellegrino, C. Ménager, F. Gazeau, and C. Wilhelm, Magnetic hyperthermia efficiency in the cellular environment for different nanoparticle designs. Biomaterials 2014, 35, 6400e6411. [4] C. Sanchez, D. El Hajj Diab, V. Connord, P. Clerc, E. Meunier, B. Pipy, B. Payré, R. P. Tan, M. Gougeon, J. Carrey, B. Gigoux, and D. Fourmy, Targeting a G-Protein-Coupled Receptor Overexpressed in Endocrine Tumors by Magnetic Nanoparticles To Induce Cell Death. ACS Nano 2014, 8 (2), 1350-1363.

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[5] V. Connord, P. Clerc, N. Hallali, D. El Hajj Diab, D. Fourmy, V. Gigoux, and J. Carrey, Real-Time Analysis of Magnetic Hyperthermia Experiments on Living Cells under a Confocal Microscope. Small 2015, 11 (20), 2437-2445. [6] R. J. Wydra, P. G. Rychahou, B. M. Evers, K. W. Anderson, T. D. Dziubla, and J. Z. Hilt, The role of ROS generation from magnetic nanoparticles in an alternating magnetic field on cytotoxicity, Acta Biomaterialia 2015, doi: 10.1016/j.actbio.2015.06.037. [7] V. T. A. Nguyen, M. Gauthier, M-C. Depaw-Gillet, and O. Sandre, Biocompatibility and in vitro cell hyperthermia toxicity of magnetic polyion complexation micelles, to be submitted.

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Recent advances on the understanding of ion adsorption/transfer in nanoporous carbon electrodes; application to supercapacitors 1 2

W.Y. Tsai1,2, P. Huang1,2, B. Daffos1,2, P.L. Taberna1,2and P. Simon1,2

UniversitĂŠ Paul Sabatier, CIRIMAT UMR CNRS 5085, F-31062 Toulouse, France RS2E, FR CNRS 3459, F-31062 Toulouse, France

The research on the design of Ionic Liquids (ILs) electrolytes for supercapacitor applications has seen a tremendous increase during the past few years. Differently from Li-batteries where the electrolyte composition and stability must fit with several requirements (SEI formation, electrochemical kinetics), there is potentially more room for breakthroughs in supercapacitors applications. This talk will firstly present results about the experimental study of the ion confinement effect on the electrochemical characterizations of nanoporous carbons. We will show that ionic liquids can be efficiently used as model electrolytes for pushing further our basic understanding of the electrolyte/carbon interactions in confined pores. In a second part, we will present results showing the successful preparation of free-standing, bulk, nanoporous carbon films with outstanding electrochemical and mechanical properties that can be used for developing high energy density flexible micro-supercapacitors.

Figures

Figure 1. Change of the electrode mass versus the charge during Electrochemical Quartz Crystal Microbalance measurements; the adsorption of anions and cations of the electrolyte can be tracked.

References [1] P. Simon and Y. Gogotsi, Nature Materials, 7 (2008) 845-854. [2] W.-Y. Tsai et al. JACS 8722â&#x2C6;&#x2019;8728 (2014) [3] J. Griffin et al, Nature Materials, June 22nd 2015 (doi: 10.1038/nmat4318).

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TNT2015 toulouse (france)

First Direct Observation of Diels-Alder Reactions on Graphene without Defects

L. Daukiya1, C. Mattioli2, D. Aubel1, S. Hajjjar-Garreau1, F. Vonau1, G. Reiter3, A. Gourdon2 and L. Simon1

Institut de Sciences des Matériaux de Mulhouse, UMR 7361-CNRS, Université de Strasbourg, France 2 Nanoscience group, CEMES CNRS-UPR 8011, Toulouse, France 3 Physikalisches Institut, Universität Freiburg, Germany

Although graphene has fascinating properties and a large potential for applications, functionalization of this highly non-reactive semiconductor with zerobandgap remains an important challenge. DielsAlder (DA) cycloaddition reactions represent a promising approach towards covalently attaching molecules to graphene. Using exfoliated graphene, the team of Robert C. Haddon has demonstrated that the D-A reaction works and is reversible [1]. They followed the reaction by Raman spectroscopy, determining the ratio of the G to D bands, which ascertained that graphene has been modified. However, this globally averaging measurement was not able to identify the locations where graphene was actually functionalized. Their seminal work raised the question if pre-existing defects (stepedges, holes,...) were necessary for enabling the DA reaction. Later, the same team published theoretical studies suggesting that only graphene edges (or holes) might be functionalized by a cycloaddition reaction but that no interior region of graphene could be modified [2]. Here, based on a LT-STM study, we present a direct visualization of DA reactions performed for some specific molecules deposited on graphene. These studies showed that the DA cycloaddition reactions can be carried out on the basal plane of graphene, even when it is free of any pre-existing defects. In the course of covalently grafting molecules to graphene, the sp2 conjugation of carbon atoms is broken up and two local sp3 bonds are created. The grafted molecules perturb the graphene lattice, generating a standing wave pattern associated to a 1,4 cycloaddition. Globally averaging spectroscopic techniques, XPS and ARPES, were used to determine the modification in the elemental composition of the samples after the reaction and to search for a possible opening of electronic bandgap of graphene.

TNT2015 toulouse (france)

Laurent.simon@uha.fr

References [1] Sarkar, S. ; Bekyarova, E. ; Niyogi, S. ; Haddon, R. C. Diels-Alder Chemistry of Graphite and Graphene : Graphene as Diene and Dienophile. J. Am. Chem. Soc. 2011, 133, 3324–3327. [2] Yang Cao, Sílvia Osuna, Yong Liang, Robert C. Haddon, and K. N. Houk. Diels–Alder Reactions of Graphene: Computational Predictions of Products and Sites of Reaction J. Am. Chem. Soc. 2013 135 (46), 17643-17649

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Electrocatalysis on shape-controlled metal nanoparticles: advances and challenges

J. Solla-Gullรณn, F.J. VidalIglesias, E. Herrero, V. Montiel jose.solla@ua.es

Institute of Electrochemistry, University of Alicante, Apdo 99, 03080 Alicante, Spain

Shape-controlled metal nanoparticles have indisputably enhanced the Electrocatalysis of several electrochemical reactions of interest both from fundamental and applied points of view [1-3]. In addition, this type of nanoparticles has remarkably contributed to a better understanding of the correlations between surface structure and electrochemical reactivity at the nanoscale. In this communication, we will discuss about recent advances in the use of shaped metal nanoparticles for different electrochemical reactions of interest, mainly those related to energy conversion applications, such as the oxidation of small organic molecules (C1 and C2) or the oxygen reduction reaction. In this regard, it is worth noting that the key point controlling the resulting electrocatalytic properties is not the particle shape but the specific surface structure of the nanoparticles. In fact, nanoparticles with a similar shape and size can have very different electrochemical properties as consequence of their different surface structure [4]. In this sense, we will also demonstrate how

Surface Electrochemistry may contribute to a detailed characterization of the surface structure of metal nanoparticles thus complementing other techniques such as Electron Microscopy or X-ray Diffraction.

References [1] J. Solla-Gullon, F. J. Vidal-Iglesias, J. M. Feliu, Annu. Rep. Prog. Chem., Sect. C: Phys. Chem., 107 (2011) 263. [2] H. You, S. Yang, B. Ding, H. Yang, Chem. Soc. Rev., 42 (2013) 2880. [3] S. E. F. Kleijn, S. C. S. Lai, M. T. M. Koper, P. R. Unwin, Angew. Chem. Int. Ed., 53 (2014) 3558. [4] F. J. Vidal-Iglesias, J. Solla-Gullon, E. Herrero, V. Montiel, A. Aldaz, J. M. Feliu, Electrochem. Commun., 13 (2011) 502.

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Exploring Edge Magnetism in Oxygen-terminated zigzag Phosphorene Nanoribbons

David Soriano1, Stephan Roche1,2

David.soriano@icn.cat

ICN2 - Institut Català de Nanociéncia i Nanotecnologia (ICN2), Campus UAB, Spain ICREA – Institució Catalana de Recerca i Estudis Avançats, Spain

Few layer black phosphorous, or phosphorene, has been attracting much attention during the last two years due to its very interesting semiconducting properties: a sizable band gap that ranges between 0.3– 2 eV depending on the number of layers, and very high carrier mobilities of around 103 cm2V-1s-1. [1] These properties makes black phosphorous one of the potential candidates, together with transition metal dichalcogenides, to lead the new generation of field-effect transistors. Similarly to graphene, cutting few layer black phosphorous along different directions leads to edge geometries that can present either metallic or insulating behavior. These edges are highly reactive and tend to adsorb chemical species during the fabrication process modifying the electronic properties of the nanoribbon [2]. In particular, phosphorene nanoribbons are prone to be oxidized when handled in ambient air.[3] Motivated by recent experimental observations of magnetism in oxidized black phosphorous antidote lattices [4], here we explore by means of firstprinciples calculations the possibility of inducing edge magnetic moments in zigzag phosphorene nanoribbons (ZZPNR). In contrast to previously reported calculations [5], we find that edge oxidation is key to achieve a strong edge magnetism out of this material, and that such magnetism is very different to that reported previously in zigzag grapheme nanoribbons.

References [1] L. Li, Y. Yu, G. J. Ye, Q. Ge, X. Ou, H. Wu, D. Feng, X. H. Chen and Y. Zhang, Nature Nanotechnology, 9 (2014) 372. [2] X. Peng, A. Copple and Q. Wei, Appl. Phys. Lett., 116 (2014) 144301.

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[3] A. Ziletti, A. Carvalho, D. K. Campbell, D. F. Coker and A. H. Castro Neto, Phys. Rev. Lett., 114 (2015) 046801. [4] Y. Nakanishi, D. Soriano, C. Ohata, R. Iwaki, Y. Fukai, K. Nomura, T. Nakamura, S. Katsumoto, S. Roche and J. Haruyama, Submitted to Nature Communications [5] Y. Du, H. Liu, B. Xu, L. Sheng, J. Yin, Z.-G. Duan and X. Wan, Sci. Rep., 5 (2015) 8921. [6] Z. Zhu, C. Li, W. Yu, D. Chang, Q. Sun and Y. Jia, App. Phys. Lett., 105 (2014) 113105.

Figures

Figure 1. Band structures of O-terminated zigzag phosphorene nanoribbons of different width. The upper panel correspond to 6l-ZZPNR and the lower one to the 10l-ZZPNR case. The Fermi level is set at E = 0. (a) and (d) are the band structures without spin. It is important to note the presence of a pair of midgap state bands. (b) and (d) are the same bands but including the spin polarization. (c) and (f) show the edge magnetic moments obtained in presence of oxygen. Interestingly, the magnetic moments order antiferromagnetically along the edges and ferromagnetically between adjacent P and O atoms.

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The synthesis of BN-nanostructures from borates of alkali and alkaline-earth metals

A.E. Steinman1, A.T. Matveev1, K.L. Faerstein1, A.M. Kovalskii1, I.V. Sukhorukova1, D.V. Shtansky1, D. Golberg2

National University of Science and Technology "MISIS", Moscow, Russia National Institute for Materials Science (NIMS), Ibaraki, Japan

Extraordinary mechanical strength and chemical inertness of boron nitride nanotubes (BNNTs) make them an attractive material for reinforcement of advanced plastics, ceramics or metals for innovative applications in aerospace, automobile and other industries. Deterrent to a wide technological use of BNNTs is their poor availability on the market. Nowadays only a few laboratories around the world have reported on the synthesis of BNNTs with different qualities in tens of grams per hour yields. Lack of practical models for the BNNTsâ&#x20AC;&#x2122; nucleation and growth is a bottleneck for their high yield synthesis. In our previous work [1] the influence of lithium oxide on reaction of boron oxide with ammonia was investigated. Obtained results suggested that lithium borates play a key role in BNNTs growth. To shed a new light on these phenomena we have studied an influence of alkali and alkaline-earth oxides (MeOx) on reaction of boron oxide with ammonia. Reactions of oxide mixtures (M2O/MO) Âˇ nB2O3, where M2O and MO are alkali and alkaline-earth oxides respectively have been explored for a molar ratio n=0,5-5 in a temperature range of 900-1250oC. It was found that various BN-nanostructures like nanoparticles, graphene-like flakes, nanotubes, and nanofibers grow dependently on borate composition and temperature. High quality straight and wellstructured BNNTs with a diameter of 30-80 nm (fig. 1) have been obtained with a high yield from Li, Mg, Ca borates in a certain range of their compositions and temperatures. Na and K borates produced exclusively BN nanoflakes in a whole studied composition and temperature ranges (fig. 2). A model for BN nanostructures nucleation and growth from borates is proposed. The obtained results are the basis for creating a highly scalable method for BN-nanostructures synthesis.

References [1] Andrei T. Matveev, Konstantin L. Firestein, Alexander E. Steinman, Andrey M. Kovalskii, Oleg I. Lebedev, Dmitry V. Shtansky, Dmitri Golberg. Boron nitride nanotube growth via boron oxide assisted chemical vapor transportdeposition process using LiNO3 as a promoter. Nano Res. Available on-line 08 Apr 2015.

Figures

Figure 1. BNNTs grown from Mg borate

Figure 2. BN nanoflakes grown from Na borate

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Crystal architecture on superconducting layered materials

Yoshihiko Takano takano.yoshihiko@nims.go.jp

National Institute for Materials Science (NIMS) 1-2-1 Sengen, Tsukuba 305-0047 Japan

High-Tc superconducting materials such Fe-based and cuprates superconductors have a layered structures as shown in fig. 1. In these compounds, superconducting layers and blocking layers are stacked alternately. Many Fe-based superconductors have been found by arranging the blocking layer so far. 11-type iron chalcogenides have the simplest crystal structure among the iron-based superconductors as they are composed of only superconducting layers. However, a small amount of excess iron exists between these superconducting layers, which suppress the superconductivity. Manipulation of excess iron is required to induce bulk superconductivity in 11 type. We have successfully developed several ways to remove the effect of excess iron from FeSe (one member of 11 type iron-based superconductors) using annealing processes. We have found that oxygen annealing suppress the excess Fe effect and can achieve bulk superconductivity in the 11 system. Alcoholic beverage annealing can also remove excess Fe and induce bulk superconductivity. A further

consequence is that the critical current density Jc is also dramatically improved by sulfur annealing. Further to this, we have recently succeeded in the inducement of superconductivity using an electrochemical reaction similar to that of a Li-ion battery. The excess iron is de-intercalated by an applied electronic current. In my presentation, I will talk in detail about crystal architectonics using electrochemical reaction and the mechanism behind the inducement of superconductivity in iron chalcogenides.

References [1] Y. Mizuguchi et al., Phys. Rev. B 81 (2010) 214510, [2] Y. Mizuguchi et al., Europhys. Lett. 90 (2010) 57002. [3] Y. Kawasaki et al., Solid State Commun. 152 (2012) 1135. [4] K. Deguchi et al., Supercond. Sci. Technol. 24 (2011) 055008. [5] H. Okazaki et al., EPL 104 (2013) 37010.

Figures

Figure 1. Schematic of crystal strucure of layered superconductos

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Enhancement of thermoelectric properties in in-plane Graphene/BN structures

Van-Truong Tran, Jérôme Saint Martin, Philippe Dollfus

van-truong.tran@u-psud.fr

IEF, Université Paris-sud, CNRS, UMR 8622, Bât 220, 91405 Orsay, France

In spite of the remarkable advantage of excellent electron transport properties [1,2], graphene has two major drawbacks with a view to thermoelectric applications. First, this material is a gapless semimetal, which makes difficult to separate the opposite contributions of electrons and holes to the Seebeck coefficient. Second, it exhibits very high lattice thermal conductivity [3]. Different strategies of nanostructuring have been suggested to open a bandgap, enhance the Seebeck coefficient and reduce the thermal conductivity of graphene, and finally to achieve good values of thermoelectric figure of merit ZT (see review [4]). In the simple case of a graphene ribbon, the highest ZT value achievable at room temperature is about 0.35 for a very narrow armchair ribbon with 3 dimer lines (MCC = 3) along the width.

References

Here, taking advantage of the fact that recently a novel form of a hybrid monolayer material of graphene and Boron Nitride has been synthesized successfully [5,6], we propose a new structure of graphene/BN, as schematized in Fig 1, expected to enhance thermoelectric performance. By means of atomistic simulation of electron and phonon transport, we show that the phonon conductance is strongly reduced in this structure because of high scattering at the edges and at graphene/BN interfaces. Additionally, a good power factor is achieved thanks to the bandgap opening in the graphene/BN regions. These combined results lead to a significant enhancement of ZT. In Fig 2, we plot ZT as a function of chemical potential for a structure of graphene width MCC = 5. A peak ZT as high as 0.81 at room temperature is obtained for a chemical energy µ = 0.41 eV, and ZT = 1.48 is even reached if three vacancies are introduced in the channel (not shown). It is remarkable that such high value can be obtained at relatively low and quite accessible chemical energy.

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[1] P.J. Zomer, S.P. Dash, N. Tombros and B.J. Van Wees, Appl. Phys. Lett. 99 (2011) 232104. [2] A.H. Castro Neto, N.M.R. Peres, K.S. Novoselov, and a. K. Geim, Rev. Mod. Phys. 81 (2009) 109. [3] A.A. Balandin, S. Ghosh, W. Bao, I. Calizo, D. Teweldebrhan, F. Miao and C.N. Lau, Nano Lett. 8 (2008) 902-907. [4] P. Dollfus, V. Hung Nguyen, J. Saint-Martin, J. Phys.: Condens. Matter 27 (2015) 133204. [5] P. Sutter, R. Cortes, J. Lahiri and E. Sutter, Nano Lett. 12 (2012) 4869–4874. [6] Z. Liu, L. Ma, G. Shi, W. Zhou, Y. Gong, S. Lei, X. Yang, J. Zhang, J. Yu, K.P. Hackenberg, A. Babakhani, J.-C. Idrobo, R. Vajtai, J. Lou and P.M. Ajayan, Nat. Nanotechnol. 8 (2013) 119-124.

Figure 1. Studied structure with BN flakes attached to a graphene ribbon in the channel. We define nBN as the number of BN/G/BN sections in the active region 1 nBN=1 nBN=2

0.8

nBN=4 nBN=8

0.6 ZT

nBN=10

0.4 0.2 0 0

0.5

1.5

µ (eV) Figure 2. Figure of merit ZT as a function of chemical potential for different values of nBN. The structure parameters are MCC = 5, MBN = 9, NVC = NBN = 8. Simulation was performed at T = 300 K.

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Molecules Affect Charge Transport in Nano-Particle Self-Assemblies, at Room Temperature 1

LPCNO, INSA, CNRS, Université de Toulouse, Toulouse, France LCC, CNRS, Université de Toulouse, Toulouse, France 3 Institut Carnot – CIRIMAT, Université de Toulouse, Toulouse, France 2

Understanding the parameters that control the transport of an electron through a molecule is a key point for applications in different fields: molecular electronics, solar cells, biochemistry, catalysis, etc. Within the scope of this project, we used metallic nano-particle self-assemblies as a tool to study the influence of the ligands (which stabilize the particles) on the electronic transport of the global assembly. We first elaborated assemblies of platinum nanoparticles with a size small enough to observe Coulomb blockade at room temperature. Such system gives us the opportunity to perform measurements on a large number of molecules, but addressing them individually (as only one electron "crosses" the molecules at a given time). We then confirmed experimentally that the distance between the particles affected the charging energy of the system, but we also proved that other parameters were also important, such as the size of the nanoparticles and the dielectric constant of the molecules.

Simon Tricard1, Olivier SaïdAïzpuru1, Donia Bouzouita1, Suhail Usmani1, Angélique Gillet1, Marine Tassé2, Guillaume Viau1, Phillipe Demont3, Julian Carrey1 and Bruno Chaudret1 tricard@insa-toulouse.fr

Our approach, based on a statistical analysis on a large number of measurements, showed the feasibility of performing meaningful charge transport measurements on non-ideal systems, i.e. not well organized, and with a large size distribution of the particles. We were indeed able to significantly distinguish an amine from a hydroxyl, or a carboxylic acid function, only by measuring an i(V) curve with a conductive AFM, and to rationalize the apparent trend, by analyzing the charging energy of the nano-particles.

References [1] [2] [3] [4] [5]

L. Grill et al., Nat. Nanotechnol. 2 (2007) 687 J. Cai et al., Nature 466 (2010) 470 L. Lafferentz et al., Nat. Chem. 4 (2012) 215 Kolmer et al., Angew. Chem. Int. Ed. 52 (2013) 10300 Kolmer et al., Chem. Comm. (2015) DOI: 10.1039/C5CC02989A

Figure 1. Platinum nano-particle assemblies in the presence of mercaptophenol: regular TEM picture and high resolution TEM picture.

Figure 2. i(V) curves of the self-assemblies with aminothiophenol, mercaptophenol, and mercaptobenzoic acid, normalized at 2V: full scale and zoom on the low voltage region.

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Probing lattice temperature in current-driven carbon nanotube fibers by Raman spectroscopy 1

LPCNO-INSA, Université de Toulouse, Toulouse, France CEMES-CNRS, UPR 8011, Université de Toulouse, Toulouse, France 3 Dept of Electrical and Computer Engineering, Rice University, Houston, Texas, USA 4 Dept of Chemical and Biomolecular Engineering, Rice University, Houston, Texas, USA 5 Dept of Chemistry, Rice University, Houston, Texas, USA 6 Dept of Materials Science and NanoEngineering, Rice University, Houston, Texas, USA 7 Dept of Physics and Astronomy, Rice University, Houston, Texas, USA 8 LNCMI-CNRS, UPR 3228, Université de Toulouse, Toulouse, France

D. Tristant1,2, A. Zubair3, D. E. Tsentalovich4, C. C. Young4, Pascal Puech2, I. Gerber1, M. Pasquali4,5,6, R. J. Headrick4,5,6, J. Kono3,6,7, J. Leotin8

Recently, an effective method has been developed for fabricating carbon nanotube (CNT) fibers with ultrahigh conductivities and current carrying capacities [1,2]. These fibers have high potential in a variety of high-power and high-current electrical applications as they have electrical conductivities close to that of copper. Under high currents, complex situations arise in these fibers, where driven electrons heat the lattice by producing nonequilibrium phonons in a time- and spacedependent manner. Quantitatively understanding such situations is crucial for optimum heat management for desired applications. Here, we use Raman spectroscopy to quantitatively determine the temperature and doping level of these CNT fibers in the presence of a high current [3]. At low frequencies, we observe radial breathing modes (RBMs), which provide information on the diameters of nanotubes in resonance. Combining the diameter and the excitation energy allows us to determine their type (metallic or semiconductor) through the Kataura plot. At high frequencies, by measuring accurately the position of the G-band as a function of current and temperature, we deduce the temperature of the lattice for both doped and undoped fibers as well as the doping level of the doped fiber.

tristant@insa-toulouse.fr

We thus estimate the temperature of the lattice from the G-band shifts versus applied current and temperature. From these data we extracted a value of 2000°C/A as the current coefficient of heating for an undoped fiber with a diameter of 20.4 µm with temperature increases below 200 K. The variation of the Stokes and Anti-Stokes intensities of different modes (inner RBMs, outer RBMs, G) with current at various exciting wavelengths is fully consistent with homogeneous heating. Moreover, by analyzing in detail a Raman spectrum for doped fibers versus undoped fibers, we estimated the Fermi level shift, ΔEF, to be about 0.7 eV. This shift modifies the behavior of the outer tube, activating new conduction channels. Our estimation of the ratio of conduction channels between doped and undoped fibers is about 4, consistent with the value of 4 reported in Ref. [2] when the fiber switches from a doped to undoped state.

References [1] Behabtu N. et al., Science 339, 182 (2013). [2] Wang X. et al. Adv. Funct. Mater 24, 32413249 (2014). [3] Steiner M. et al, Nat. nanotechnol. 4, 320-324, (2009)

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Operation Mechanism and Novel Functions of gapless-type atomic switches based on metal oxide and polymer thin film

Tohru Tsuruoka, Cedric Mannequin, Karthik Krishnan, and Masakazu Aono TSURUOKA.Tohru@nims.go.jp

International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan

As the downscaling of dynamic random access and flash memories approach the physical limit, new solutions for volatile/nonvolatile storages are being investigated at both the research and industry levels. Among several emerging technologies, resistive switching memory based on cation transport in a thin ionic conductor film is one of the most attractive candidates for the next-generation memory technology. Because of its similarity to the operation mechanism of a ‘gap-type atomic switch’, in which resistance across a nanometer gap between a mixed conductor electrode and an inert counter electrode is controlled by the formation and dissolution of a metal bridge under bias voltage sweeping [1], cationmigration-based resistive memories are referred to as a ‘gapless-type atomic switch’ [2]. We have investigated the operation mechanism of Cu, Ag/metal oxide/Pt atomic switch cells using Ta2O5 as a model system and demonstrated their unique functions, which cannot be realized by conventional semiconductor switches. Ta2O5-based cells exhibit bipolar resistive switching behavior under bias voltage sweeping. They are SET from a high-resistance state (HRS) to a low-resistance state (LRS) at positive bias to an electrochemically active metal electrode (Ag or Cu), and RESET from LRS to HRS at negative bias. The SET process corresponds to the formation of a metal filament by nucleation on the inert counter electrode (Pt), while the RESET process is attributed to the dissolution of the metal filament due to thermochemical reactions [3]. It was found that residual water in the oxide film plays a crucial role in redox reactions of Cu(Ag) and resistive switching behavior [4], in relation to the film morphology [5]. The cell also exhibited conductance quantization and synaptic/memristive

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behaviors, as shown in Fig. 1, which indicate potential for use in neural computing systems [6]. We also demonstrated that an atomic switch can be realized using a silver-conductive solid polymer electrolyte (SPE) [7]. An Ag/SPE/Pt cell, fabricated with a mixture of poly(ethylene oxide) (PEO) and Ag salt, showed bipolar resistive switching under bias voltage sweeping, similar to oxide-based atomic switches. We also successfully fabricated cells with a junction size of 50 μm on a plastic substrate using an inkjet-printed SPE film [8]. The fabricated cells showed stable switching behavior upon substrate bending (Fig. 2), which indicates their great potential for flexible switch/memory applications. Variations in the operation voltages by temperature and ambient pressure suggested the importance of the crystallinity and water uptake ability of the matrix PEO on the resistive switching behavior. A detailed switching mechanism will also be discussed from observations for a planar cell structure [9].

References [1] Terabeat al., Nature 433(2005) 47. [2] T. Hasegawa et al., MRS Bull. 34(2009) 929. [3] T. Tsuruokaet al., Nanotechnology 21(2010) 425205;ibid.22 (2011) 254013. [4] T. Tsuruoka et al., Adv. Funct. Mater. 22 (2012) 70; ibid. (2015, in press). [5] C. Mannequin et al., Nanotechnology (submitted). [6] T. Tsuruoka et al., Nanotechnology 23(2012) 435705; Mater. Res. Soc. Symp. Proc. 1562 (2013). [7] S. Wu et al., Adv. Funct. Mater. 21 (2011) 93. [8] S. R. Mohapatra et al., AIP Adv. 2(2012) 022144; J. Mater. Chem. C (2015, published online). [9] Karthik Krishnan et al., ACS Nano (submitted).

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Figures

Figure 1. Synaptic behavior of a Ta2O5-based atomic switch

Figure 2. SPE-based cells fabricated on a plastic substrate and their switching behavior under substrate bending

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Magnetolasmonic nanoantennas metamaterials: news and views

P. Vavassori p.vavassori@nanogune.eu

CIC nanoGUNE, 20018 San Sebastian and IKERBASQUE Basque Foundation for Science, 48011 Bilbao (Spain)

The rapidly developing field of magneto-plasmonics merges the concepts from plasmonics and magnetism to realize novel and unexpected phenomena and functionalities for the manipulation of light at the nanoscale. Ferromagnetic nanoantennas support localized plasmons and exhibit magneto-optical activity under external magnetic fields. The fundamentals aspects of the physics underlying the optical behavior of magneto-plasmonic nanoantennas arising from the intertwined optical and magnetooptical properties have been in large part clarified [1-5]. In this talk I will show recent directions in the field of magneto-plasmonic nanoantennas, which involve the control of optical interaction by placing nanoantennas in close proximity or arranging them on periodic bi-dimensional arrays. Initial results show that indeed near field interactions between closely spaced nanoantennas (dimers, trimers, and chains) [6] or diffractive coupling leading to collective plasmonic surface lattice resonances in arrays (Rayleigh anomaly) [7], induce large and controllable modifications of the magneto-optic response of such metamaterials (see Fig. 1). Similar promising results are being observed in arrays of ferromagnetic nano-antidots [8]. A review of the most significant, although preliminary, discoveries in this area as well as simple initial modeling efforts

developed to understand the essential physics involved, will be briefly presented. Such multifunctional magneto-plasmonic metamaterials may open new views towards applications to variety of emerging technologies as, e.g., magnetoplasmonic rulers (dimers that are able to report the nanoscale distances) [6], ultrasensitive molecular sensing (see Fig. 2) [9] and ultrathin optical metadevices (flat nano-optics).

References [1] J. Chen et al., Small 7, 2341 (2011) [2] V. Bonanni et al., Nano Lett. 11, 5333 (2011) [3] N. Maccaferri et al., Phys. Rev. Lett. 111, 167401 (2013) [4] N. Maccaferri et al., Opt. Express 21, 9875 (2013) [5] K. Lodewijks et al., Nano Lett. 14, 7207 (2014) [6] I. Zubritskaya et al., Nano Lett. 15, 3204 (2015) [7] M. Kataia et al., Nature Commun. 6, 7072 (2015) [8] N. Maccaferri et al., in preparation [9] N. Maccaferri et al., Nature Commun. 6, 6150 (2015)

Figures

Figure 1. Effects of diffractive coupling on the optical and magneto-optical properties of ferromagnetic nanoantennas: a) disordered arrangement of Ni elliptical nanoantennas; b) ordered array of identical Ni elliptical nanoantennas.

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Figure 2. Light polarization manipulation enabled by phase compensation in the optical response of a magnetoplasmonic Ni nanoantenna and its exploitation for ultrasensitive sensing.

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Preparation and performance of few layer graphene in energy storage applications

Khaled Parvez, Tetiana Kurkina, Mingjie Zhong, Teressa Nathan-Walleser and Shyam S. Venkataraman

BASF SE, Ludwigshafen, Germany

In BASF, advanced carbon materials are being investigated for several potential fields of application such as electronics, catalysis, and energy storage and conversion devices. Graphene, one such advanced and emerging carbon material has recently spurred strong interest of scientific research both in academia and industry owing to its remarkable properties. Owing to its higher electrical conductivity, few layer graphene (FLG) is proposed as a new carbon material to replace or complement traditional carbon black additives in lithium-ion batteries (LIB) as well as activated carbon in supercapacitor devices. Additionally FLG â&#x20AC;&#x201C; silicon composite

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materials is proposed as potential anode material for LIB applications. The presentation will focus on two aspects: (i) synthesis and characteristics of FLG and graphene oxide via electrochemical route and (ii) performance of FLG in supercapacitor and LIB devices. Finally the talk will present the challenges lie ahead for the commercialization of FLG to make it to reality in the near future.

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DNA-Programmed Assembly of Molecules and Materials

Kurt Vesterager Gothelf kvg@chem.au.dk

Center for DNA Nanotechnology (CDNA), iNANO and Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark

We are using DNA as a programmable tool for directing the self-assembly of molecules and materials. The unique specificity of DNA interactions and our ability to synthesize artificial functionalized DNA sequences makes it the ideal material for controlling self-assembly and chemical reactions of components attached to DNA sequences. Recently, we applied these methods to DNA templated conjugation of DNA to proteins such as antibodies.[1] In particular we are using DNA origami, large self-assembled DNA structures as a template for positioning of materials such as organic molecules, dendrimers and biomolecules.[24] We have also used DNA origami to image chemical reactions with single molecule resolution[4] and to make a 3D DNA origami box

with a controllable lid.[5] The main focus of the presentation will be on a recently prepared conjugated DNA-phenylene vinylene polymer and its self-assembly on DNA origami for studies of electronic and optical properties (Fig 1).

References [1] Rosen et al. Nature Chem. 2014, 6, 804–809. [2] Ravnsbæk; J. B et al. Angew. Chem. Int. Ed. 2011, 50, 10851–10854. [3] Liu, H. et al. J. Am. Chem. Soc. 2010, 132, 18054-18056. [4] Voigt, N. V. et al. Nature Nanotech. 2010, 5, 200-205. [5] Andersen, E. S. et al. Nature 2009, 459, 73-76.

Figures

Figure 1. Illustration and AFM image of poly(DNA-phenylene vinylene) on DNA origami.

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Molecules meet Si: bridging singlemolecular function with practical device

Yutaka Wakayama WAKAYAMA.Yutaka@nims.go.jp

International Center for Materials Nanoarchitectonics (WPI-MANA) National Institute for Materials Science (NIMS) 1-1 Namiki, Tsukuba, Japan

Our main purpose is to develop an electron tunneling devices by taking advantages of molecular functions. A key point of this study is to integrate organic molecules into Si-based device architecture. Here, we present the process to prepare a metal-oxide-semiconductor (MOS)device with molecules, fundamental mechanism of electron tunneling [1], multi-level tunneling through multiple molecules [2], and optical control of electron tunneling via photochromic molecules for optoelectronic device [3]. For practical development, quantum dots for the electron tunneling devices should be well designed on nanometer scale. For example, the size of the quantum dots should be a few nanometers for realizing room temperature operation. Size uniformity is another important factor for fine control of threshold voltage (Vth). To meet these requirements, we adopted organic molecules as quantum dots. First, fullerene (C60) molecules were embedded in a MOS structure (Fig. 1(a)). Staircases in current-voltage curves were observed in a double-tunneling junction consisting of Au/Al2O3/C60/SiO2 multi-layers on Si(100) substrates. Here, C60 and Al2O3, SiO2 layers served as intermediate electrodes and tunneling barriers, respectively. We elucidated that the observed staircases can be attributed to resonant tunneling through the empty and occupied energy levels of the C60 molecules. The energy diagram is drawn in Fig. 1(b). These results clearly indicate that the Vth for electron tunneling can be tuned precisely as requested by designing molecular structure.

different energy levels were embedded together in MOS structure. For optical switching, reversible photochromic reaction (open-ring/closed-ring isomerization) of diarylethene was applied to optical control of electron tunneling. Importantly, our device configuration is compatible with the conventional MOS-FET device and, therefore, these results demonstrate the potential of practical use of molecules for the tunneling devices in the Si-based devices, such as singleelectron memory and tunneling transistor.

References [1] R. Hayakawa, N. Hiroshiba, T. Chikyow, Y. Wakayama, Adv. Func Mater., 21(2011) 29332937. [2] H.-S. Seo, R. Hayakawa, T. Chikyow, Y. Wakayama, J. Phys. Chem. C, 118 (2014) 64676472. [3] R. Hayakawa, N. Hiroshiba, T. Chikyow, Y. Wakayama, K. Higashiguchi, K. Matsuda, ACS Appl. Mater.& Inter., 5 (2013) 11371-11376

We applied this mechanism to various functional tunneling manipulation those are multi-level tunneling and optical switching of electron tunneling. In the multi-level tunneling, heterogeneous phthalocyanine molecules with

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Figures

Figure 1. (a) Device and molecular structures, (b) Energy diagram of resonant tunneling

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september 07-11, 2015

TNT2015 toulouse (france)

Graphene for energy solutions

Di Wei di.wei@nokia.com

Nokia R&D UK c/o University of Cambridge, 21 JJ Thomson Av., CB3 0FA, Cambridge, UK.

A review presentation focuses on the applications of graphenes in electrochemical energy storage devices that Nokia R&D UK has developed. It covers from the liquid based graphene manufacturing to the application of graphene inks in batteries and supercapacitors. Recent progress in electrochemical exfoliation of graphene is also covered. We also demonstrated that even monolayer graphene has the power to light up an LED [4] and graphene is a more robust electrode in batteries than traditional graphite [5]. This work is part of the recent EU Graphene Flagship Pilot, which was granted 1 billion EURO by European Committee.

References

Figures

Figure 1. a) Graphene inks b) and c) Structure and image of the rechargeable lithium battery based on grapheneink cathode and polymer electrolyte. Figure 2 Monolayer graphene battery lights up LED

[1] Di Wei, Hongwei Li, Dongxue Han, Qixian Zhang, Li Niu, Huafeng Yang, Piers Andrew and Tapani Ryhänen, , Nanotechnology, 22 (2011) 245702. [2] D. Wei, P. Andrew, H. Yang, Y. Jiang, W. Ruan, D. Han, L. Niu, C. Bower, T. Ryhanen, M. Rouvala, G. A J Amaratunga, and A.Ivaska J.Mater. Chem., 21 (2011) 9762. [3] Di Wei, Lorenzo Grande, Vishnu Chundi, Richard White, Chris Bower, Piers Andrew and Tapani Ryhänen, Chem.Commun., 2012, 48 (9), 1239 – 1241. [4] Di Wei et al., J.Mater. Chem.,A.. 2013, 1, 31773181. [5] Di Wei et al. Nanoscale.. 2014, 6,9536.

Figure 2. Monolayer graphene battery lights up LED

TNT2015 toulouse (france)

september 07-11, 2015

| 137

Designing Gold Nanoparticles for Biomedical Applications: Insights from Theoretical Simulations

Irene Yarovsky, Patrick Charchar, Nevena Todorova irene.yarovsky@rmit.edu.au

RMIT University, GPO Box 2476, Melbourne, Australia

Biomolecules adsorb differently to nano-structured materials and this phenomenon is being now widely exploited for engineering novel materials and devices for biomedical applications. At the same time, there is little knowledge of how engineered nanomaterials interfere with the overall biological molecular machinery [1]. Theoretical modelling can help get insights into the molecular mechanisms of biomolecular interactions of nanomaterials which can help improve molecular recognition needed for safe and efficient biomedical applications. However, some serious challenges exist in developing an adequate approach to modelling nano-bio systems with rigor and efficiency [2]. In this talk examples of our recent simulations performed in conjunction with experimental studies will be presented. These include: (1) effects of nano-structuring on protein adsorption to monolayer protected Au nanoparticles [3, 4]; (2) effects of peptide surface density on the efficiency of TAT peptide functionalised Au nanoparticles for membrane internalisation [5]; (3) effects of structure and dynamics of the functional peptide layer on the efficiency of epitope conjugated Au nanoparticles for biosensing [6].

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september 07-11, 2015

References [1] M.P.Monopoli, C. Aberg, A. Salvati, K.A. Dawson, Nature Nanotechnology 7 (2012) 779. [2] A.J. Makarucha, N. Todorova, I. Yarovsky, Eur. Biophysics Journal, 40 (2011)103. [3] A. Hung, S. Mwenifumbo, M. Mager, J. Kuna, M. Hembury, F. Stellacci, I. Yarovsky, M. M. Stevens, Journal of the American Chemical Society, 133 (2011) 1438. [4] A. Hung, M. Mager, M. Hembury, F. Stellacci, M. M. Stevens, I. Yarovsky, Chem. Sci., 4 (2013) 928. [5] N.Todorova, C. Chiappini, M. Mager, B. Simona, Imran Patel, M. M. Stevens, I. Yarovsky, Nano Lett. 14 (2014) 5229. [6] H. Andersen, M. Mager, M. Griebner, P. Charchar, N. Todorova, N. Bell, G. Theocharidis, S. Bertazzo, I. Yarovsky, M.M. Stevens, Chem. Mater., 26 (2014) 4696.

TNT2015 toulouse (france)

Mechanism of alkali metal insertion into TiO2 polymorphs

M. Zukalova, B. Laskova and L. Kavan marketa.zukalova@jh-inst.cas.cz

J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, CZ-18223 Prague 8, Czech Republic

TiO2 (anatase) and TiO2(B) (monoclinic polymorph of TiO2) are attractive candidates for anodes in rechargeable Li-ion batteries, due to their cycling stability, reasonable capacity and operating potential. Li insertion into TiO2 polymorphs proceeds as a diffusion controlled process, where the peak current in cyclic voltammogram scales with square root of the scan rate. Excess Li can be accommodated either at the surface of the nanometer-sized particles or at the open channels in the structure of particular polymorphs by a pseudocapacitive faradaic process, which is not controlled by diffusion. In this case, currents in the peaks of cyclic voltammograms of Li scale with the first power of scan rate.

(perpendicular to (010) face). Deeper insight into differences between charging mechanisms of TiO2(B) and anatase during Li+ insertion provides analysis of cyclic voltammograms of Li insertion. The ratio of capacitive contributions to overall charge of Listorage was found to be over 30% higher in TiO2(B) compared to that in anatase nanocrystals [2]. The predominant pseudocapacitive process in TiO2(B) was related to accommodation of Li inside the TiO2(B) open channels in monoclinic lattice.

Li-insertion electrochemistry of TiO2(B) is basically different from that of anatase. Accommodation of Li in the TiO2(B) lattice manifests itself by two pairs of peaks in cyclic voltammogram with formal potentials of ca. 1.5 and 1.6 V. Zukalova et al [1] found that Li-insertion into TiO2(B) is characterized by unusually large faradaic pseudocapacitance. This peculiar effect was ascribed to Li+ accommodation in open channels of TiO2(B) structure allowing fast Li-transport in TiO2(B) lattice along the b-axis

References

TNT2015 toulouse (france)

This work was supported by the Grant Agency of the Czech Republic (contracts No. 13-07724S and 15-06511S).

[1] Zukalova, M.; Kalbac, M.; Kavan, L.; Exnar, I.; Graetzel, M. Chemistry of Materials, 17, 5, (2005), 1248-1255. [2] Laskova, B.; Zukalova, M.; Zukal, A.; Bousa, M.; Kavan, L. Journal of Power Sources, 246, (2014), 103-109.

september 07-11, 2015

| 139

L. Assaud, H. Vergnes, D. Evrard, L. Salvagnac, V. Conédéra, L. Noé P. Gros, P. Temple‐Boyer, M. Monthioux

Caussat, Brigitte

S. Ponce‐Alcántara, A. Griol, L. Bellieres, J. García‐Rupérez

Caroselli, Raffaele

J.‐F. Bryche, F. Hamouda, J. Ruscica, R. Gillibert, J. Moreau, M. Lamy de la Chapelle, M. Canva, B. Bartenlian

Barbillon, Gregory

L.M. Lacroix, F. Ott, G. Viau

Anagnostopouloui, Evangelia Eleni

Se Hee Lee, Ga‐Young Park, Gna Ahn, Eunji Lee and Yang‐Hoon Kim

Ahn, Ji-Young

De, Amitabha and Pintu Sen

Agnihotri, Nidhi

Ankan Dutta Chowdhury, Amitabha De

Agnihotri, Nidhi

authors

Posters list: alphabetical order

France

Spain

France

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country

Graphene & 2D / Carbon nanotubes

NanoOptics / NanoPhotonics / Plasmonics / Nanophononics

Nanomagnetism and Spintronics

NanoChemistry

Nanomaterials for Energy

Graphene & 2D / Carbon nanotubes

topic

"Catalytic CVD synthesis of a graphene-based microelectrode as a biosensor"

"Nanoporous silicon photonic structures for the development of ultrasensitive biosensors"

“Soft UV Nanoimprint Lithography designed Plasmonic Substrates for Bimodal Biodetection”

“Scale-up synthesis & alignment of magnetic nanowires via polyol process: A bottom-up approach for nanostructured rare-earth free permanent magnets”

"A Single-Step Microfluidic Synthesis of Microspheres Immobilized with ssDNA Probes"

“Conducting PEDOT and Polyaniline Based Metal Oxide Nanocomposites as Efficient Supercapacitor”

"β-Cyclodextrin functionalized graphene based nonenzymatic electrochemical detection of cholesterol "

poster title

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student

senior

student

senior

student

student senior

Only Posters submitted by registered participants and payment processed are listed below (as of 01/09/2015)

Spain

Switzerland

Ghassen Dridi and Christian Joachim

Faizy Namarvar, Omid

Julio Bastos‐Arrieta, Joan de Pablo e Ignasi Casas

Espriu Gascon, Alexandra

Humberto Rodríguez‐Solla, Antolin Hernández Battez, Rosana Badía Laíño, Marta Elena Díaz García

Espina Casado, Jorge

Nitin Goyal, Martin Debiasio, Andreas Kenda

Dusari, Srujana

Mélanie Gauvin, Thomas Alnasser, David Babonneau, Alessandro Coati, Benoit Viallet, Jérémie Grisolia, Guillaume Viau and Laurence Ressier

Digianantonio, Lucas

Lin Yang, Jean‐Christophe Cau, Emmanuel Flahaut, Christophe Vieu

Delagarde, Aude

M. Barteri, G. Berardi, F. A. Scaramuzzo

De Angelis, Francesca

Aymerich

France

Spain

Austria

France

Italy

Qian Wu, Marc Porti, Montserrat Nafria, Xavier Spain

Claramunt Ruiz, Sergi

Hisila Santacruz Ortega, Rosana Badía Laíño, Marta Elena Díaz García

Chimeno Trinchet, Christian

Ugo Cataldi, Patric Oulevey, Jakob Bierwagen, Thomas Bürgi

Chekini, Mahshid

Theory and modelling at the nanoscale

Other

NanoChemistry

Graphene / Carbon nanotubes

Nanostructured and nanoparticle based materials

Graphene & 2D / Carbon nanotubes

Nanobiotechnologies & Nanomedicine

Graphene & 2D / Carbon nanotubes

NanoChemistry

NanoOptics / NanoPhotonics / Plasmonics / Nanophononics

senior

student

“Preparation and characterization of Pd-NPs doped UO2 samples: nanotechnology approaches to evaluate the behavior of spent nuclear fuel in deep geological repositories”

“Parallel Quantum Circuit in a Tunnel Junction”

student

senior

student

senior

student

“Functional ZrO2 nanoparticles as lubricant additives”

"Interface study of graphene on AlGaN/GaN heterostructures using Raman Spectroscopy"

“Characterization of the effect of humidity on nanoparticle based strain gauges using small angle xray scattering coupled with electromechanical measurements”

"Automated patterning of Nanocarbons inks using magnetic Micro Contact printing"

“Internalization of core-shell superparamagnetic nanoparticles into granulocytes”

"Evaluation of ultra-thin structures composed of graphene and high-k dielectrics for resistive switching memory applications"

"Functional CuO and ZnO nanoparticles using water-inoil reverse micelles"

"Large-scale nano-structured templates for enhancing fluorescence and Raman spectroscopy"

Wilfried Solo Ojo, Nicolas Hallali, Julian Carrey, Bruno Chaudret, Sébastien Lachaize, Fabien Delpech, Céline Nayral

Glaria, Arnaud

M.A. Casado, M.I. Vázquez, I. Llamas, R.J. Contreras, J.M. López‐Romero, J. Benavente

Gelde Rubia, Lourdes

V. Romero, I. Llamas, V. Vega, J. García, V.M. Prida, B. Hernando, J. Benavente

Gelde Rubia, Lourdes

T. Alnasser, J. Grisolia, B. Viallet, S. Xie, J. Brugger and L. Ressier

Gauvin, Melanie

Valentim, P. T., Vasco, J. P., Fonseca, H., Borme, J., Assis, P.‐L., Rodrigues, W. N., Quivy, A. A., Guimarães, P. S. S.

Gaspar, João

C. Garcia‐Marcelot, L.‐M. Lacroix, K. Soulantika, P. Fau, B. Chaudret t

Garnero, Cyril

A. Ballestar, P. Godignon, J. M. de Teresa, R. Ibarra

García-García, Alberto

Kazunari Matsuda, Philippe Tamarat & Brahim Lounis

Gandil, Morgane

Victor Neto

Gabriel, Barbara

J. G. Croissant, S. Alsaiari, B. A. Moosa, D. H. Anjum and N. M. Khashab

Fatieiev, Yevhen

France

Spain

France

Portugal

France

Spain

France

Portugal

Saudi Arabia

NanoChemistry

Nanostructured and nanoparticle based materials

NanoOptics / NanoPhotonics / Plasmonics / Nanophononics

NanoChemistry

Graphene & 2D / Carbon nanotubes

Other

Nanobiotechnologies & Nanomedicine

"Magnetic Hyperthermia with Fe@SiO2 Nanoparticles. Synthesis and Efficiency"

“Inclusion of silver nanoparticles for improving regenerated cellulose membrane performance”

“Fabrication and analysis of ions diffusive transport through nanoporous ceramic membranes: Influence of pore size, porosity and surface material”

"Free-standing self-assembled monolayered nanoparticle membranes and their electromechanical properties by conducting AFM"

"Nanofabrication of silicon nitride photonic crystals membranes"

"Chemical synthesis of FeCo nanoparticles: size and shape control"

"Influence of SiC substrate modification on the growth of epitaxial graphene"

“Magneto-photoluminescence spectroscopy of bright and dark excitons in isolated semiconducting singlewalled carbon nanotubes”

“An analysis tool for decision making support on nanomaterials applications - a preliminary case study”

“Photoresponsive Bridged Silsesquioxane Nanoparticles with Tunable Morphology for Light-Triggered Plasmid DNA Delivery ”

senior

student

senior

student

senior

student

Jae Man Yoo, Yong Hyup Kim

Lee, Jeong Seok

P. Fau, M., Kahn, M. Comtat, P. Behra, B. Dubreuil, K. Fajerwerg

Lebon Tailhades, Emilie

L. Noé, M. Monthioux, B. Caussat

Lassègue, Pierre

S. Viarbitskaya, A. Teulle, J. Sharma, A. Thete, A. Cuche, A. Bouhelier, A. Arbouet, G. Colas des Francs, C. Girard, E. Dujardin

Kumar, Upkar

V. Kovalishyn, L. Charochkina, N. Abramenko (Golovina), W. Peijnenburg, L. Metelitsya

Kopernyk, Iryna

Jeong Seok Lee, Yong Hyup Kim

Kim, Taewoo

Sulmaz Poreskandar, Shima Maghsoodlou

Khodaparast Haghi, Akbar

Mahendra Rai

Ingle, Avinash

S. Jaziri

Hichri, Aida

M.D. Fernández, M.J. Fernández

Hernandez Aldave, Sandra

Katerina Soulantika, Philippe Serp, Bruno Chaudret, Adrien Berliet, Antoine Fécant, Sylvie Maury

Harmel, Justine

Korea

France

Ukraine

Korea

Iran

India

Tunisia

Spain

France

Graphene & 2D / Carbon nanotubes

Nanostructured and nanoparticle based materials

Graphene & 2D / Carbon nanotubes

NanoOptics / NanoPhotonics / Plasmonics

Risks‐toxicity‐regulations

Graphene & 2D / Carbon nanotubes

Theory and modelling at the nanoscale

Nanobiotechnologies & Nanomedicine

Graphene & 2D / Carbon nanotubes

NanoChemistry

“High-performance CNT line emitters using the macroscopic mechanical clamping process”

“Gold electrodes functionalized with silver nanoparticles: an original and promising route for nitrate sensing in seawater ”

“Iron nanoparticles deposited on ozone pre-treated carbon nanotubes by Fluidized Bed Metal Organic Chemical Vapor Deposition”

“Multimodal plasmonics in crystalline colloidal systems”

“Prediction of toxicity for metal oxide nanoparticles”

"Facile and Fast Fabrication of Cylindrical Graphene Field Emitters"

"Trends in Mathematical modeling of electrospun Nanofibers"

“Chemosynthesized copper nanoparticles: an effective fungicidal agent against plant fung”

"Neutral and Charged excitons in Tungsten Dichalcogenoides Monolayer"

"Synthesis and characterization of graphene-Ag nanoparticles hybrids"

"Synthesis of model cobalt catalysts for Fischer Tropsch Synthesis"

senior

student

senior

student

W‐S. Ojo, S. Xu, B. Chaudret, F. Delpech

Nayral, Céline

Sang‐Beak Kim

Na, Byung-Ki

Mariam Barawi, Robert Biele, Eduardo Flores, José R. Ares, Carlos Sánchez, Gabino Rubio‐ Bollinger, Nicolás Agraït, Roberto D’Agosta, Isabel Ferrer and Andres Castellanos‐Gomez

Molina-Mendoza, Aday J.

Arvydas Čiegis, Andrius Vasiliauskas, Kęstutis Šlapikas, Rimantas Gudaitis, Sigitas Tamulevičius

Meskinis, Sarunas

Mariana Castrillón García, Cristina Crespo, José Alberto Lorda

Meier, Johann G.

F. Carcenac, C. Thibault, L. Malaquin, E. Trévisiol, C. Vieu

Marchand, Raphaël

D. Dova, A. Guerrini, C. Carrara, P. R. Thakare, M. Galli, C. Sangregorio, S. Cauteruccio, M. Panigati, E. Licandro, R. Pennati, F. Orsini, P. Arosio, A. Lascialfari

Maggioni, Daniela

Juan José Sáenz, Manuel I. Marqués

Luis Hita, Jorge

B. Schoeters, B. Partoens and F. M. Peeters

Leenaerts, Ortwin

J. H. Choi, J.‐Y. Huh, I. Kim, T. Sung Lee, D. Seok Jeong, W. S. Lee and W. M. Kim

Lee, Kyeong-Seok

France

Korea

Spain

Lithuania

Spain

France

Italy

Spain

Belgium

Korea

NanoChemistry

Nanomaterials for Energy

Low dimensional materials (nanowires, clusters, quantum dots, etc.)

NanoOptics / NanoPhotonics / Plasmonics / Nanophononics

Nanostructured and nanoparticle based materials

Nanobiotechnologies & Nanomedicine

senior

“RT Synthesis of Air-Stable and Size-Tuneable Luminescent ZnS coated Cd3P2 Nanocrystals with High Quantum Yields”

student

“Electrochemical Characteristics of Nano-size Li4Ti5O12/C as Anode Materials of Lithium-ion Battery”

"Electronic bandgap and exciton binding energy of layered semiconductor TiS3"

senior

“Polar and apolar thermoplastic polymers nanocomposites with WS2-nanotubes and of Mo6S2I8nanowires: Preparation, thermal and mechanical properties” "Plasmonic Diamond Like Carbon Nanocomposite Films and Nanostructures"

student

senior

student

senior

"A versatile silicon platform for electrical recording of ion channels activity"

“Iron Oxide-PNA Nanoparticles for miRNA targeting”

"Theoretical Analysis of Dimers' Diffusion in Optical Lattices"

NanoOptics / NanoPhotonics / Plasmonics / Nanophononics Nanobiotechnologies & Nanomedicine

"New structures for two-dimensional III-V binary compounds"

"Mid-infrared plasmonic nanoantennas fabricated by diffuse photonic nanojet lithography"

Graphene & 2D / Carbon nanotubes

NanoOptics / NanoPhotonics / Plasmonics / Nanophononics

Bermúdez P., Colominas C.

Sempere, Bernat

T. Zimmermann, A. Knecht, R. Richter, T. Höhne, M. I. S. Röhr, J. Petersen, R. Mitric and T. Möller

Rander, Torbjörn

Prathap Haridoss, Chandra P. Sharma

R, Hindumathi

Andrés Castellanos‐Gomez, Gabino Rubio‐ Bollinger and Nicolás Agräit

Quereda, Jorge

E.V.Vershinina

Popov, Vladimir

José Lorenzo Balenzategui, C. Morant, E. Elizalde

Pinilla Yanguas, Sergio

M. Martinez‐Calderón, I. Castro‐Hurtado, M. Gomez‐Aranzadi, A. Rodríguez, S.M. Olaizola, E. Castaño, G. Gª Mandayo

Palomares Iñiguez de Ciriano, Usue

Andreas Meyer, Tobias Vossmeyer

Olichwer, Natalia

Li Qin Zhou, Raul Simões, Bárbara Gabriel, Qi Hua Fan

Neto, Victor

Saeed Rayati

Nejabat, Fatemeh

Spain

Germany

India

Spain

Russia

Spain

Germany

Portugal

Iran

Graphene & 2D / Carbon nanotubes

Low dimensional materials (nanowires, clusters, quantum dots, etc.)

Graphene & 2D / Carbon nanotubes

Nanostructured and nanoparticle based materials

Nanomaterials for Energy

Nanofabrication tools & nanoscale integration

Nanostructured and nanoparticle based materials

Nanomaterials for Energy

NanoChemistry

senior

student

“Nobel Photocatalytic Method to observe grain boundaries of large-area graphene on Copper by optical microscopy”

student

senior

student

senior

student

"Investigating nanoplasmonics in diamondoid-metal cluster hybrids"

"Synthesis and Characterization of Novel Nano-Cocoon like Structures of Polymer-CNT Nanocomposite"

"Strain engineering of Schottky barriers in single and few-layer MoS2 vertical devices"

“Study of the Possibility of Nanodiamond Particles Transformation into Carbon Onions in Metal Matrix Composites when Heated in Non-Oxidizing Conditions”

“Carbon nanotube net as a conductive and transparent film for solar energy conversion”

“Laser Induced Nanostructures on ZnO Thin Films for Morphology-controlled Gas Detection”

"Chemiresistors Based on Gold Nanoparticle Supercrystals: Sensing Mechanism Studied by in situ GISAXS"

"Novel conductive ZnO:Zn composites for thin film solar cell back reflectors application"

"Application of colloidal metalloporphyrin nanoparticles in catalytic oxidation reactions "

Todri-Sanial, Aida

P. Gaillard

Thuillier, Hubert

Maya Nandkumar,Vignesh Muthuvijayan, Ramesh Parameswaran

Thampi, Sudhin

Stefan Facsko, Adrian Keller

Teschome, Bezu

Nikita Toropov, Rezida Nabiullin

Starovoytov, Anton

A. R. Vilchis‐Nestor, V. Sánchez‐Mendieta, M. Á. Camacho‐López

Silva, Luisa

Dennis Lehr, Daniel Voigt, Stefanie Kroker, Ernst‐Bernhard Kley and Andreas Tünnermann

Siefke, Thomas

Ayoung Park, Sangyeon Lee, Gowoon Shim, and Jinseo Kim

Seo, Hyungtak

Myung‐Ho Kim, Young‐Ahn Lee, Jinseo Kim, Duck‐Kyun Choi

Seo, Hyungtak

Wonji Jung, Yong Hyup Kim

Seo, Dongkyun

Katharina Luka‐Guth, Matthias Wieser, Lokamani, Jannic Wolf, Manfred Helm, Sibylle Gemming, Jochen Kerbusch, Elke Scheer, Thomas Huhn and Artur Erbe

Sendler, Torsten

France

India

Germany

Russia

Mexico

Germany

Korea

Germany

Theory and modelling at the nanoscale

Graphene & 2D / Carbon nanotubes

Nanobiotechnologies & Nanomedicine

Other

NanoOptics / NanoPhotonics / Plasmonics / Nanophononics NanoOptics / NanoPhotonics / Plasmonics / Nanophononics

NanoOptics / NanoPhotonics / Plasmonics / Nanophononics

Low dimensional materials (nanowires, clusters, quantum dots, etc.)

Graphene & 2D / Carbon nanotubes

Low dimensional materials (nanowires, clusters, quantum dots, etc.)

"Carbon nanotube interconnects for energy efficient integrated circuits"

"Graphene Production: CANOE’s Response for Industrial needs"

“Prevention of bacterial adhesion onto electrospun fibroporous poly(carbonate) urethane membrane by embedding Graphene oxide”

"Topography-Controlled Alignment of DNA Origami Nanotubes on Nanopatterned Surfaces"

"Modification of the Photonic Properties of Cyanine Thin Films by Near Fields of Plasmonic Nanostructures"

“Biogenic silver nanoparticles as selective sensors for copper (ii) and lead (ii) ions”

“Wire grid polarizer basing on interband absorption in the deep ultra violet spectral range”

“Effective and Stable H doping in ZnO by Photochemical Radical Insertion”

"Photochemical Metallic Conduction Channel Creation in InGaZnO by H Radical Doping"

"Density controllable graphene aerogel for enhanced supercapacitor performance"

“Light-Induced Switching of Tunable Single-Molecule Junctions”

senior

student

senior

student

senior

student

S. Rafiei, A. K. Haghi

Ziaei, Maryam

Younes Makoudi, Judicael Jeannoutot Simon Lamare, Frank Palmino and Frederic Cherioux

Zhan, Gaolei

M. A. Migahed , A. M. Al‐Sabagh, E.A. Khamis

Zaki, Elsayed

O. Couturaud, W. Desrat, D. Kazazis, A. Michon, M. Pierre, M. Goiran, W. Escoffier and B. Jouault

Yang, Ming

Y. Piñeiro, C. Vazquez‐Vazquez, C. Rodríguez, M.A. López‐Quintela and J. Rivas

Vargas, Zulema

Aisylu N. Kamalieva, Tigran A. Vartanyan

Toropov, Nikita

Iran

France

Egypt

France

Spain

Russia

Theory and modelling at the nanoscale

NanoChemistry

Other

Graphene & 2D / Carbon nanotubes

Nanobiotechnologies & Nanomedicine

NanoOptics / NanoPhotonics / Plasmonics / Nanophononics

student

“Research challenges, future trends and limitations in modeling and simulation of electrospun carbon nanofibers”

senior

student

senior

"Adsorption of 4-(4"-bromophenyl)-(4’-pyridyle) benzene molecules on Si (111)-B and Cu (111)"

“Quantum chemical calculations Synthesis and corrosion inhibition efficiency of ethoxylated -[2-(2-{2-[2-(2Benzenesulfonylamino-ethylamino)-ethylamino]ethylamino}-ethylamino)-ethyl]-4-alkyl-benzenesulfonamide on API X65 steel surface under H2S environment ”

"High field magneto-transport in Graphene Grown by Chemical Vapor Deposition on SiC"

"Magnetic nanocomposites based on mesoporous silica for biomedical applications"

“Thin films of organic dyes with silver nanoparticles: enhancement and spectral shifting of fluorescence due to excitation of localized surface plasmons”

Conducting PEDOT and Polyaniline Based Metal Oxide Nanocomposites as Efficient Supercapacitor a

Pintu Sen and Amitabha De

E-mail of corresponding author: amitabha.de@saha.ac.in a

Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata 700064, India Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064, India

A nanocomposite material comprising of nanaoparticles of inorganic transition metal oxides and conducting polymer like poly 3,4-ethylenedioxythiophene (PEDOT) and Polyaniline (PANI) can act as very efficient supercapacitor with enhanced specific capacitance value due to synergistic effect. Here we used nanaoparticles of two different metal oxides i.e. nickel ferrite (NiFe2O4) and manganese dioxide (MnO2) to combine separately with PEDOT or PANI to form nanocomposite electrodes to investigate their electrochemical behavior as supercapacitor. Nanocrystalline nickel ferrite was synthesized by sol-gel method from stoichiometric amount of their nitrates and ÄŽ- MnO2 nanorod by redox reaction between stoichiometric quantities of MnSO4 and KMnO4 in aqueous medium. Reverse micro emulsion polymerization in n-hexane medium was adopted for PEDOT nanotube formation using different surfactants. The PANIÂąMnO2 nanocomposite was chemically synthesized by oxidative polymerization of aniline using FeCl3 under controlled conditions in presence MnO2 nanorod. Structural morphology and characterization for the nanocomposites were studied using XRD, SEM, TEM, IR and XPS. Their electrochemical performances were tested using cyclic voltammetry at different scan rates (2-20mV/s) and galvanostatic charge-discharge at different constant current densities in acetonitrile containing 1M LiClO4 electrolyte. Both the Nanocomposite electrodes showed higher specific capacitances; for PEDOTNiFe2O4 (251 F/g) in comparison to NiFe2O4 (127 F/g) and PEDOT (156 F/g) and for PEDOT-MnO2 (315 F/g) and PANI-MnO2 (221 F/g) respectively compared to MnO2 (158 F/g) where morphology of the pore structure plays a significant role over the total surface area. AC impedance measurements were done to ascertain contribution of pseudocapacitance in the frequency range 10 kHz to 10 mHz with a potential amplitude of 5mV.

d) 0.001

I ( A / cm )

c) 0.000

-0.001

0.0

0.2

0.4

0.6

Volt ( V )

0.8

1.0

Cyclic voltammogram of PEDOTÂąMnO2 composite in acetonitrile containing 1M LiClO 4 electrolyte at a scan rate (a) 2mV/s, (b) 5mV/s, (c) 10 mV/s (d) 15 mV/s and (e) 20 mV/s in a potential range between 0.6 and Âą0.6 V.

Typical cyclic voltammogram of (a) PEDOT-Aq (b) PEDOT-Org (c) Nano NiFe2O4 and (d) PEDOT-NiFe2O4 composite electrodes in acetonitrile containing 1 M LiClO4 electrolyte at a scan rate 2mV/s in a potential range between 0 to 1V.

ȕ-Cyclodextrin functionalized graphene based non-enzymatic electrochemical detection of cholesterol Nidhi Agnihotri, Ankan Dutta Chowdhury, Amitabha De* Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata, West Bengal 700064, INDIA nidhi.agnihotri@saha.ac.in Abstract Cholesterol and its esters are membrane constituents widely found in biological systems which serve a unique purpose of modulating membrane fluidity, elasticity, and permeability making the cell walls rigid and strong. In the human serum, 80% of cholesterol exists in the ester form with normal level of 200mg/dL. The higher levels of cholesterol lead to life-threatening coronary heart diseases, cerebral thrombosis and atherosclerosis. Therefore, cholesterol level in the serum is one of the most important parameters in diagnostics and prevention of heart diseases. The electrochemical approach for biosensing has gained momentum over various analytical methodologies due to their high sensitivity and fast response time. A lot research has been performed around the electrochemical biosensing of cholesterol by the enzymatic reaction of cholesterol with cholesterol oxidase, where the concentration of either H2O2 generated or oxygen consumed during the enzymatic reaction is being monitored. Detection selectivity in most of these methods relies on the use of cholesterol selective enzymes which are expensive and prone to denaturation. The optical sensors are highly appreciable as an alternative for simple and cost effective methods, whereas an electrochemical non-enzymatic sensing process has an ample scope for better sensitivity. ȕ-cyclodextrin ȕ-CD) is a cyclic oligosaccharide consisting of 7-ȕ ±4) glucopyranose units, with internal cavity lined with C(3)H and C(5)H hydrogen and ether-like oxygen providing a hydrophobic environment. This internal cavity RI ȕ-CD allows hydrophobic cholesterol molecules to be soluble in aqueous solution, WKDW¶V why ȕ-CDs have a high affinity for sterols as compared to other lipids in vitro. Herein, we have presented a non-enzymatic electrochemical approach for cholesterol sensing using Graphene-ȕ-Cyclodextrin (Grp-ȕ-CD) hybrid system as the sensing matrix. Grp-ȕ-CD solution was synthesized in situ where graphene oxide (GO) sheets were treated ZLWK ȕ-CD in presence of ammonia and Sodium hydroxide ȕ-CD is presumed to get covalently attached over GO sheets during the reaction forming GO-ȕ-CD followed by its reduced using hydrazine forming Grp-ȕ-CD. Methylene Blue (MB), a redox indicator, when added into the Grp-ȕ-CD solution, forms a host±guest complex ZLWK ȕ-CD. When cholesterol solution was added in the solution, it replaced the MB molecule from the cavity due to its higher DIILQLW\ WRZDUGV ȕ-CD, offering better detection sensitivity range via selective host±guest interaction. Graphene sheet network helps in rapid transfer of the electrochemical signal. As MB is a well known redox probe and hence can be easily detected using Differential Pulse Voltammetery (DPV) technique. To the best of our knowledge this is for the first time, a completely non-enzymatic sensing with such a high sensitivity and low detection limit is being reported, using an electrochemical DPV metric method with the targeted analyte, cholesterol. Salient features of the present study include graphene's increased solubility DIWHU ȕ-CD functionalization, due to the covalent interactions occurring between the hydrophilic surfaces of the two and using DPV technique, where cholesterol molecule is replacing MB molecule and forming the inclusion complex within the hydrophobic core of Grp-ȕ-CD. The detection limit of cholesterol was achieved as low as 1 mM. Also, it detects cholesterol efficiently in the micromolar concentration range with outstanding selectivity over the common interfering species. References [1] G.-C.Zhao, J.-J. Zhu, J.-J. Zhang, H.-Y.Chen, Anal. Chim. Acta, 394 (1999) 337±344. [2] G. Zhang, S. Shuang, C. Dong, J. Pan. Spectrochim. Acta A:Mol. Biomol. Spectrosc., 59 (2003) 2935±2941. [3] A. Mondal, N.R.Jana, Chem. Commun., 48 (2012) 7316±7318. [4] Y. Guo, S. Guo, J. Ren, Y. Zhai, S. Dong, E. Wang, ACS Nano, 7 (2010) 4001±4011.

Figures:

A singleǦstep Microfluidic Synthesis of Microspheres Immobilized with ssDNA Probes Se Hee Lee, GaǦYoung Park, Gna Ahn, Eunji Lee, YangǦHoon Kim and JiǦYoung Ahn* Chungbuk National University, 1 ChungdaeǦro, SeowonǦgu, Cheongju, 362Ǧ763, Republic of Korea jyahn@chungbuk.ac.kr Abstract Aptamers are short and single strand DNA (ssDNA) oligonucleotides capable of ligand binding in 1 variety of biological assays . They can be obtained by in vitro selection according to the SELEX procedure. The generation and isolation of ssDNA from the amplified sub-DNA pools are essential to make DNA aptamer. Asymmetric PCR method has been used to generate ssDNA in SELEX. However, since both ssDNA and double strand DNA (dsDNA) are usually generated, additional separation experiments are necessarily required such as a strepatavidin-biotin separation. In this study, we fabricated PDMS microfluidic device that includes microsphere generator (X-junction). Polyacrylamide solution was applied to microfluidic device with acrydite modified oligonucleotides 2 DNA probe [Figure 1] . The main challenge of the use of polyacrylamide is in the covalent immobilization of ssDNA probes onto the microbead surfaces. In addition, the three-dimensional configuration of the microspheres can improve the complementary binding between DNA-DNA to the surface. DNA probe immobilization and their extension were confirmed by using fluorescent labeled complement partner [Figures 2]. Our microspheres are available to use ssDNA generation, DNA fishing and DNA microarray analysis. References [1] R. Stoltenburg, C. Reinemann, B. Strehlitx, Biomelecular Engineering, 4(2007) pp. 381-403 [2] Farah N. Rehman et al., Nucleic Acids Research, 2(1999) pp.649-655 Figures

Figure 1. Schematic diagram of PDMS microfluidic device and Polyacrylamide Microbeads

Figure 2. 3-Dimensional configuration of the microspheres and ssDNA probe (a) To confirm immobilization and extension of ssDNA probes onto microbeads, antisense oligonucleotide was used. The fluorescence signal was observed by using confocal laser scanning microscope (b). These result showed that oligonucleotides were exposed to surface of microbeads generated by microfluidic device.

Scale-up synthesis & alignment of magnetic nanowires via polyol process: A bottom-up approach for nanostructured rare-earth free permanent magnets 1

E. Anagnostopoulou , L.M. Lacroix , F. Ott , G. Viau 1

UniversitĂŠ de Toulouse, LPCNO, UMR 5215 INSA-CNRS-UPS, 135 av. de Rangueil 31077 Toulouse, France 2 Lab. LĂŠon Brillouin UMR 12 CEA/CNRS Centre dÂś(WXGHV GH 6DFOD\ *Lf sur Yvette Cedex, France anagnost@insa-toulouse.fr

Abstract The numerous mechanical and green energy applications of rare-earth permanent magnets, as well as WKHLU OLPLWHG VXSSO\ OHG WR WKH VWXG\ RI QRYHO SHUPDQHQW PDJQHWV EDVHG RQ PDWHULDOVÂś VKDSH DQG magnetocrystalline anisotropy. The present work describes the synthesis of high aspect ratio magnetic cobalt nanoparticles through the polyol method, which provides good control of the particles shape, size and crystal structure. Manipulating the synthesis conditions that influence the nucleation and growth step we obtained anisotropic nanoparticles, monodisperse in size, with diameter and length in the range 10-20 nm and 50-200 nm respectively (fig.1a) [1]. Such building blocks are promising candidates for permanent magnet applications, since their long axis is parallel to the c axis of a well crystallized hcp structure. Aiming to the production of a macroscopic magnetic material, we developed the scale up of the polyol process for the synthesis of tens grams of cobalt nanorods. Since the key for a high energy product is the alignment of its building blocks packed with a high volume fraction [2], we aligned the Co nanowires under an external magnetic field (1T). The resulting dense and highly textured macroscopic magnetic structure (fig. 1b,c) provided squared magnetization loops with Mr/Ms higher than 96% and Âľ0Hc of 0.5 T (fig. 2a). Detailed analysis of the nanowires orientation and organization in their macroscopic magnetic structure was evidenced by Small Angle Neutron Scattering measurements. Thanks to the combination of the magnetic and thermogravimetric ananlysis, the magnetic cobalt volume fraction could be determined. The B(H) curve and the corresponding (BH)max could then be -3 deduced (fig. 2b), with a maximum obtained value of (BH)max at 160 kJ.m .

(a)

(c)

(b)

M/Ms

(a)

0.5

Âľ0H (T)

0 -2

-1

(b)

B (T)

Figure 1: (a) TEM image of Co nanowires (d=22 nm, l=160 nm) ; (b) macroscopic magnetic structure as a result of the nanowires alignment ; (c) SEM image of the same rods.

1 0

-1000

-500

-0.5 -1

0 -1

|| ŮŁ

500

1000

Hc (kA/m)

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Figure 2: (a) Hysteresis loops of the Co macroscopic magnetic structure measured with the applied field parallel and perpendicular to the alignment ; (b) B(H) loop of the same Co nanowires.

References [1] Soumare, Y. et al., Adv. Func. Mater., 19 (2009) 1971-1977. [2] Panagiotopoulos, I. et al.,J. Appl. Phys., 114 (2013) 143902.

Soft UV Nanoimprint Lithography designed Plasmonic Substrates for Bimodal Biodetection. a

a,b

G. Barbillon , J.-F. Bryche , F. Hamouda , J. Ruscica , R. Gillibert , J. Moreau , c b a M. Lamy de la Chapelle , M. Canva , B. Bartenlian a

Institut d’Électronique Fondamentale - Université Paris-Sud, Orsay, 91405, France. Laboratoire Charles Fabry - Institut d’Optique Graduate School, CNRS, Palaiseau, 91127, France. c Laboratoire de Chimie, Structures, Propriétés de Biomatériaux et d’Agents Thérapeutiques (CSPBAT) - Université Paris 13, Bobigny, 93017, France. gregory.barbillon@u-psud.fr b

Abstract Soft lithography is well-known to be useful for biological applications. They are compatible with insulating support and with the necessity to obtain large area of nanostructures [1]. To do that, the soft UV-assisted Nanoimprint Lithography (UV-NIL) is used [2,3]. In this work, the fabrication of bimodal plasmonic substrates obtained by soft UV-NIL and reactive ion etching (RIE), is optimized in order to 2 2 obtain large arrays (from some mm to cm ) of gold nanodisks on gold film. These samples allow two modes of optical characterization of biomolecular targets: the Surface Plasmon Resonance Imaging (SPRI), for quantification, and the Surface-Enhanced Raman Scattering (SERS) effect, for spectroscopic identification. Firstly, the master mold is patterned (nanodisk arrays) by electron beam lithography (NanoBeam nB4) on a silicon substrate. RIE processes have been optimized to transfer the pattern in the Si master mold. Indeed, we demonstrated that the verticality of the hole walls has an effect on the fabrication of the PDMS stamps. The next step is the imprint process through the AMONIL resist with PDMS stamps. A bilayer AMONIL-MMS4 / PMMA 950K [2] is deposited by spin-coating on the gold film in order to remove the AMONIL resist after the UV curing and to obtain a good lift-off process. The imprint in AMONIL (Figure 1(a)) was performed with an EVG620 equipment using a mercury lamp at 365 nm wavelength. The etching processes of AMONIL and PMMA have been optimized to transfer the pattern. For this fabrication, the etching is stopped at the level of the gold film. Then, a gold layer (30 nm) is evaporated on this gold film, and the remaining PMMA/AMONIL bilayer is removed via the lift-off process. The gold nanodisks were obtained for diameters varying from 100 to 500 nm by step of 50 nm with a periodicity of 600 nm (Figure 1(b): example of nanodisks obtained by soft UV-NIL), and also for a periodicity of 400 nm with diameters varying from 100 nm to 300 nm. In order to valid our fabrication process, the samples were used to detect chemical molecules (here, Thiophenol molecules) by SPRI and SERS. The SERS signal is improved by a factor 10 compared to gold nanodisks directly on Si or glass substrates together with a good sensitivity for SPRI measurements. References [1] M. Cottat, N. Lidgi-Guigui, I. Tijunelyte, G. Barbillon, F. Hamouda, P. Gogol, A. Aassime, J.-M. Lourtioz, B. Bartenlian, M. Lamy de la Chapelle, Nanoscale Research Letters 9 (2014) 623. [2] G. Barbillon, F. Hamouda, S. Held, P. Gogol, B. Bartenlian, Microelec. Eng. 87 (2010) 1001-1004. [3] F. Hamouda, H. Sahaf, S. Held, G. Barbillon, P. Gogol, E. Moyen, A. Aassime, J. Moreau, M. Canva, J.-M. Lourtioz, M. Hanbücken, B. Bartenlian, Microelec. Eng. 88 (2011) 2444-2446.

(a)

(b)

Figure 1. SEM images, the dimensions of the presented example are: diameter = around 200 nm, and the periodicity = 600 nm: (a) Imprint in AMONIL, and (b) gold nanodisks on gold film obtained by soft UV-NIL.

redox couples. And the entire system becomes more efficient with a high methanol tolerance and at the same time the use of precious metals could be eliminated. CONCLUSION We have demonstrated that mesoporous fullerene with well-ordered structure, high surface area and conductivity can be prepared by nano-hard templating approach wherein mesoporous silica was used as template. The prepared materials were found to be excellent electrodes for super capacitor application, which could be due to the high surface area together with the highly conducting wall structure. These features promote the electron transport between the wall structure of the materials and the current collectors. It was also found that the mesoporous fullerenes are highly stable even after 1000 cycles, revealing high electrochemical stability. In addition, we produced a new metal-free catalyst by replacing the expensive noble metals which was then used as an electro-catalyst for DMFC that exhibited a high methanol tolerance. Apart from this, we have also successfully synthesized the mesoporous fullerene C 70 materials for the first time with a highly crystalline nature which was examined for its material property and also showed amazing performances in the methanol tolerance test that could be used in DMFCs. References [1] Kroto, H. W et al. Nature 318 (1985) 162. [2] Hasobe, T. Phys. Chem. Chem. Phys., 12 (2010) 44

0 .46Âľ

1 43 0

Mespoporous fullerene with rod shaped morphology Figure 1: Schematic representation of the fabrication of Mesoporous fullerenes. ACKNOWLEDGEMENT One of the authors, M. Benzigar acknowledges Dr. Jeonghum Kim and centre for microscopy and microanalysis for providing the state of the art microscope facilities. A. Vinu is grateful to ARC for the award of Future fellowship.

Nanoporous silicon photonic structures for the development of ultrasensitive biosensors R. Caroselli, S. Ponce-Alcántara, A. Griol, L. Bellieres, J. García-Rupérez* Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain * jaigarru@upvnet.upv.es Abstract We present the development of a high index contrast nanoporous silicon platform to be used for the creation of ultrasensitive nanophotonic biosensing structures. In this work, we aim at mimicking the configuration of SOI (Silicon on Insulator) platform, where a thin high index top silicon layer sitting on a low index silicon oxide lower cladding is used in order to provide a high confinement of the light within the photonic structures created in the top silicon layer. A limiting factor in the sensitivity of traditional planar photonic sensing structures based on a high index contrast configuration is the fact that only the evanescent field propagating outside of the photonic structure is used for sensing purposes, while the majority of the optical field distribution associated with the guided mode is within the structure itself. On the other hand, there is an increasing interest on the use of porous silicon for the development of sensing structures, since this platform provides a higher surface/volume ratio as well as the possibility of infiltrating the target analytes directly into the pores in order to obtain an increased sensitivity. With these ideas in mind, we have worked on the optimization of a porous silicon bilayer with a refractive index profile similar to that of a SOI wafer in order to be able to have a high confinement of the light and a much reduced size of the photonic structures, while significantly increasing the sensitivity. In order to be able to obtain a high refractive index of the top layer, where the photonic sensing structures will be created, reduced size pores (with diameters lower than 8 nm) have been created. The optimization of the fabrication process for obtaining this nanoporous bilayer configuration has mainly involved the analysis of the effects of the hydrofluoric acid concentration, the current density applied, the wafer resistivity and the process time. Furthermore, the reduction of the stress between the layers has also been studied, resulting in mechanically more stable structures. By using the Bruggeman’s model [1], we have estimated the refractive index of the nanoporous silicon layers after optimizing the electrochemical fabrication process, achieving values of 3.23 and 1.78 for the optical layer and the lower cladding respectively. E-beam lithography has then been used to create the photonic structures onto this nanoporous silicon platform, successfully being able to transfer the designed layout to the top high index porous silicon layer. Funding of the Spanish government through the TEC2013-49987-EXP project is acknowledged. References [1] W.M. Merrill, et al., IEEE Trans. Antennas Propag, 47 (1999) 142-148. Figures

SEM images of (left) the nanoporous silicon bilayer and (right) a ring resonator created onto this platform using e-beam lithography.

Catalytic CVD synthesis of a graphene-based microelectrode as a biosensor

L. Assaud1,2,3, H. Vergnes1, D. Evrard2, L. Salvagnac3, V. Conédéra3, L. Noé4 2

P. Gros , P. Temple-Boyer , M. Monthioux , B. Caussat

1,*

CNRS, INPT/ENSIACET, Laboratoire de Génie Chimique, 4 allée Emile Monso, 31432 Toulouse, France 2 Université de Toulouse, UPS, Laboratoire de Génie Chimique, 118 route de Narbonne, 31062 Toulouse, France 3 Laboratory for Analysis and Architecture of Systems, CNRS-UPS Toulouse, 7 avenue du Colonel Roche, 31031 Toulouse, France 4 CEMES, UPR 8011 CNRS, University Toulouse III, 31055 Toulouse, France *

brigitte.caussat@ensiacet.fr

The oxidative stress is a biological process which is suspected to be related to the early stages of serious pathologies such as cardiovascular and neurodegenerative diseases or cancers. Thus, the development of reliable sensors for the monitoring of biomarkers involved in oxidative stress could prevent the development or early detect such pathologies. Among them, electrochemical sensors present advantages such as accuracy, reliability and low cost. In this way the electrode surface functionalization must be treated with great attention, since it will influence the sensor lifetime, sensitivity, selectivity and limit of detection. Glassy carbon is today frequently used, but this material is hardly compatible with silicon technologies required to massproduce integrated microcells. Two-dimensional materials have emerged as rapidly rising stars in the field of nanotechnology. Indeed, graphene exhibits exceptional properties in terms of mechanical resistance, conductivity, highsurface area or electrochemical stability. In the present work, graphene is synthesized by catalytic chemical vapour deposition (CVD) on large-scale area (Fig. 1). Platinum, under the form of either foil or thin film deposited onto oxidized silicon wafer, is utilized as catalyst whereas methane is used as carbon feedstock. The graphene deposition has been performed at 1,040°C at atmospheric pressure, in a home-made reactor. The resulting graphene layer has been analyzed by scanning and transmission electron microscopies as well as by Raman spectroscopy. The graphene-based electrode has subsequently been functionalized by electrografting of 4thiophenylbenzene diazonium combined with electropolymerization of EDOT. The electrochemical characterization shows a high selectivity during the simultaneous detection of ascorbic acid and uric acid (Fig. 2). These preliminary results open an interesting way of using graphene-based electrode with respect to silicon micro-technologies compatibility, for a low-cost and mass production of integrated micro-electrodes.

Figure 1- Graphene flakes synthesized by CVD onto platinum surfaces.

Figure 2- Detection of ascorbic acid and uric acid by cyclic voltammetry in phosphate buffer electrolyte.

Large-scale nano-structured templates for enhancing fluorescence and Raman spectroscopy Mahshid Chekini, Ugo Cataldi, Patric Oulevey, Jakob Bierwagen, Thomas BĂźrgi Department of Physical Chemistry, University of Geneva, Quai Ernest-Ansermet 30, Geneva, Switzerland mahshid.chekini@unige.ch

In recent years potential applications of metallic nanoparticles as an efficient source of light, heat and energetic electrons at the nanoscale regime attract a lot of attention and lead to their extensive study. The collective oscillations of electrons in metal nanoparticles as a result of electromagnetic interaction with light, or so called nDQRSDUWLFOHVÂś SODVPRQ UHVRQDQFHV, can be tuned by altering their size, shape, surrounding medium and even their assemblies or spatial arrangement. Their unique light interaction and recent advances in their syntheses and application paved the way toward their use in chemical, biological and therapeutics fields. Their strong interaction with light (absorption, scattering and electromagnetic field confinement) found application in sensing, detection and enhanced spectroscopy, particularly as a nanoantenna to enhance luminescence, fluorescence and Raman scattering signals [1,2,3]. Here we present our attempts to design and fabricate nano-structured templates. We used two different facile bottom-up approaches for preparation of plasmonic templates. The templates were prepared by charge driven assemblies of nanoparticles on different functionalized surfaces. Later these structures were modified by LBL (layer-by-layer) and seeded growth methods to alter the interparticle distance of nanoparticles and enhance their ability in enhancing fluorescence and surface enhance Raman spectroscopy. The LBL method was applied in order to provide a well-defined distance between the fluorescent dye layer and the gold nanoparticles arrays [4,5]. We investigated the plasmon-enhanced fluorescence of single array and double arrays of gold nanoparticles. A maximum of a 99-fold increase in the fluorescence intensity of the dye layer sandwiched between two gold nanoparticle arrays is found. The interaction of the dye layer with the plasmonic system causes a spectral shift in the emission spectrum and a decrease of fluorescence lifetimes in presence of nanoparticle arrays. However the lifetime increased with increasing distance between the dye and gold nanoparticle arrays. Several templates were fabricated by seeded-growth method to study a Raman active Nile-blue A fluorophore. Applying the growing steps led to increase of nanoparticles size and change of their inter-

particle distance. We observed a noticeable enhancement (averaged over the sample) due to the tuning of the QDQRSDUWLFOHVÂś SODVPRQ with the excitation laser line at optimal growth step. These nanostructures were further investigated by scanning electron microscopy and UV-Vis. By applying 4 and 5 steps of growing, we observed a plasmon resonance red shifted to the NIR and the aggregation of the closest neighbors into larger and more elongated particles via the SEM micrographs (Figure1). Preliminary attempts were also done on flexible substrates by applying a mechanical stress for plasmonic-tuning.

References [1] PK Jain, X Huang, IH El-Sayed, MA El-Sayed, Accounts of chemical research, 41 (2008) 1578-1586. [2] JR Lakowicz, K Ray, M Chowdhury, H Szmacinski, Y Fu, J Zhang, K Nowaczyk, Analyst, 133 (2008) 1308. [3] LM Liz-MarzĂĄn, Langmuir, 22 (1) (2006), 32. [4] S Muhlig, D. Cialla, A Cunningham, A Marz, K Weber, T Burgi, F Lederer, C Rockstuhl, J Phys Chem C.118 (19) (2014)10230. [5] E Jang, KJ Son, WG Koh, Colloid Polym Sci; 292 (6) (2014) 1355.

Figure1: Top left: Scheme of field enhancement as a result of plasmon resonances. Bottom left: The SEM micrograph of SERS templates without growth (left) and after fifth growth (right, scale bar 100 nm). Bottom right: The enhanced Raman and fluorescence spectra of large-scale templates.

Functional CuO and ZnO nanoparticles using water-in-oil reverse micelles 1

Christian Chimeno Trinchet , Hisila Santacruz Ortega , Rosana Badía Laíño , Marta Elena Díaz 1 García 1

Department of Physical and Analytical Chemistry, University of Oviedo, Av. Julián Clavería 8 33006, Oviedo, Spain medg@uniovi.es 2 Department of Polymers and Materials Research, University of Sonora. Mexico

Abstract Nanoparticles have deserved considerable attention in the last decade as additives in lubricating oils to reduce friction and wear between two rubbing surfaces [1]. Conventional nanoparticle additives are easily oxidized, block oil pipelines and may sediment. Consequently, the development of new chemically stable nanoparticles with improved tribological properties is an area of paramount technological interest. In this work, we describe the synthesis of CuO and ZnO nanoparticles in water-in-oil microemulsions [24] in order to control the size and morphology of the nanoparticles [Figure 1]. Functionalization of these nanoparticles was performed by a reverse titration method in which a microemulsion prepared using NH3(aq) as aqueous media and other microemulsion containing an aqueous solution of the metal salt were mixed. During the mixing, a continuous stirring was used to keep the solution clear. After 30 min reaction and aging for 24 h, a blue (for copper) or a white (ZnO) precipitate was obtained, which was dried by heating the system at 70-80ºC. The functionalization was done using a hydrocarbon chain, trimethoxy(octyl) silane which, in turn, was a functional group of the micellar structure [Figure 2]. This approach allowed D µRQH-pot¶ UHDFWLRQ: nanoparticle synthesis and its concomitant functionalization as the microemulsion droplets acted as nanoreactors. The synthetized nanoparticles were characterized by FTIR, TEM and fluorescence. As can be seen (Figure 3), TEM images of CuO nanoparticles revealed that individual particle is near spherical in shape with average nanoparticle size of ca. 7 nm. In addition, the powder showed good dispersity. References [1] D. Kim and L.A. Archer, Langmuir 27, Nanoscale organic-inorganic hybrid lubricants (2011) 3083-3094 [2] Dongyun Han et al, Powder Technology 185, Controlled synthesis of CuO nanoparticles using TritonX-100-based water-in-oil reverse micelles (2008) 286-290 [3] Tamara V. Gavrilovic et al, Scientific Reports 4:4209 Multifunctional Eu GdVO4 nanoparticles synthesized by reverse micelle method (2014), 1-9

- and Er /Yb

-doped

[4] Vuk Uskokovic and Miha Drofenik, Surface Review and Letters, Vol12, No. 2, Synthesis of materials within reverse micelles (2005), 239-277

FIGURES

Figure 1. Synthesis of CuO nanoparticles inside of reverse micelle

Figure 2. Structure of the functional reverse micelles

Figure 3. TEM image of CuO nanoparticles. Size and morphology

Evaluation of ultra-thin structures composed of graphene and high-k dielectrics for resistive switching memory applications Qian Wu, Sergi Claramunt, Marc Porti, Montserrat Nafria, Xavier Aymerich Electronic Engineering Department, Universitat AutĂ˛noma de Barcelona, Cerdanyola del VallĂ¨s 08193, Spain sclaramunt@uab.cat Abstract Nowadays the electronic industry is reaching a point that in order to keep up with the Mooreâ&#x20AC;&#x2122;s law is necessary the introduction of novel materials and think about new kind of architectures. This is especially important in memory applications, as the present non-volatile memory technology soon will have to be replaced by an alternative. One option is the Resistive Random Access Memory (RRAM) technology [1], based in the formation and destruction of conductive filaments (CF) in insulators [2], being this phenomenon called Resistive Switching (RS). By using high-k dielectrics like HfO2 in a future will be possible to integrate this technology at industrial level, as the fabrication of these structures follows the same CMOS fabrication process like the silicon technology. Moreover, the combination of this technology with other novel materials, like graphene [3], could boost its performance. In this work, prototypes of structures composed of graphene and ultrathin polycrystalline HfO2 are evaluated (Fig.1a) for memory applications. First of all, polycrystalline HfO2 of 5 nm was fabricated by Atomic Layer Deposition (ALD) over silicon substrates. Graphene grown by the Chemical Vapour Deposition (CVD) method is transferred over the substrate by the standard procedure. Then, Au/Ti 2 square shaped HOHFWURGHV RI [ Č?P are fabricated using photolithography techniques. Finally the samples were etched by O2 plasma using a Reactive Ion Etching (RIE) process in order to eliminate the graphene material that not is underneath the metal electrodes (Fig. 1b). Samples without graphene were also prepared, which are considered as reference. Then the samples were electrically analysed using a 4-probe station. The electrical analysis of the reference samples show that the capacitor structure reaches high current levels (RI Č?$) even at low voltages (Fig. 2a), suggesting the existence of conductive paths even without any forming process. These conductive paths, which didnâ&#x20AC;&#x2122;t show any RS phenomenology, could be related to the presence of grain boundaries, due the high cristanillity of the sample, which were already observed to be leaky sites in Metal-Insulator-Semiconductor (MIS) structures based on such dielectrics [4]. On the other hand, on the structures with graphene between the top electrode and the HfO2 layer, the device is somehow protected and currents of Č?$ are only reached (Fig. 2b) when forming voltages of ~5V are applied. These results indicate that graphene may favour in some cases the control of the CFs present in the dielectric, and ultimately the RS phenomenon. References [1] R. Waser et al., Nat. Mater. 6 (2007) 833-840 [2] Y.Yang et. al, Nano Lett. 9 (2009) 1636-1643 [3] K.S. Novoselov et.al., Science, 306 (2004) 666-669. [4] V. Iglesias et. al., J. Vac. Sci. Technol. B, 29 (2011) 01AB02. Figures 1E-4

HfO2 Si (b) Au/Ti Electroddes

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Fig 1. (a) Scheme of the Graphene/HfO2/Si structures fabricated. (b) Final device configuration.

Fig 2. (a) Curves obtained from the structures without graphene and (b) with graphene.

Internalization of core-shell superparamagnetic nanoparticles into granulocytes a,b

F. De Angelis , M. Barteri , G. Berardi , F. A. Scaramuzzo a

Dpt. of Anatomy, Histology, Forensic Medicine and Orthopaedics,”Sapienza” University of Rome, Via b A. Borelli 50, 00165, Rome, Italy; Center for Life Nano Science@Sapienza, Istituto Italiano di c Tecnologia, Viale Regina Elena 291, 00161, Rome, Italy; Dpt. of Chemistry, ”Sapienza” University of d Rome, P.le Aldo Moro 5, 00185, Rome, Italy, Dpt. of Basic and Applied Sciences for Engineering, “Sapienza” University of Rome, Via A. Scarpa 16, 00161, Rome, Italy. f.deangelis@uniroma1.it Nanoparticles are for definition those materials that have at least one dimension smaller than 100 nm and that can find employment in biomedical field because of their peculiar features different from the corresponding bulk materials. The main purpose of nanobiotechnology and nanomedicine is the synthesis and application of nanomaterials in the treatment of different diseases, including tumors. The peculiar physico-chemical features of materials at the nanoscale make them suitable tools for diagnosis and therapy and so for their employment as theranostic agents. Superparamagnetic nanoparticles of Fe3O4, for example, can be used as MRI contrast agents and once administrated can be confined in a 1 particular region of the body by the application of an external magnetic field , while Au nanoparticles can be exploited not only as contrast probes in optical imaging, but also as therapeutic agents if their 2 surface is engineered with receptor proteins, antibodies and drugs . Nanoparticles (NPs) can find application both in vitro and in vivo experiments but one of the major problems in living organism are the rapid clearance performed by the immune system, the accumulation in the reservoir organs such as liver, lung and spleen and consequently the low NPs concentration that reaches the tissue of interest. It is known that the NPs properties such as their size, shape, surface charges and functionalization can 3 affect their distribution within the body and one of the most studied problems is the formation of the protein corona on their surface that may influence not only their properties but also the role of the linked 4 molecules . Many stratagems have been employed to avoid the lost of active nanoparticles concentration through the functionalization with polymers (PEG), peptides and proteins, but not too many successes have been achieved. To overcome this drawback, a new approach to the use of nanoparticles as theranostic agents has been developed by engulfing nanoparticles into the same cells (leukocytes) that are appointed to remove from the blood flow foreign bodies, such as pathogens, cellular debris, and in this case circulating nanoparticles. More in details this new delivery strategy is 5 refereed as the Trojan Horse method , and consists in incubating engineered nanoparticles with ex vivo leukocytes cells and in their following readministration to patient. In this way it could be possible to avoid many of NPs application side effects and it might allow to reach regions of tumors that are inaccessible through the EPR effect (enhanced permeability and retention effect) commonly exploited to deliver nanomaterials into tumoral tissues. In this context we synthesized, characterized and studied the engulfment of multitasking superparamagnetic nanoparticles (MNPs) of Fe3O4@Cu@Au into human granulocytes. NPs had been 6 previously functionalized with methotrexate (MTX) and folic acid (FA) (fig.1), respectively a chemotherapeutic drug and a vitamin which is a MTX structural isomer. We chose to synthesize this type of core-shell nanoparticles because they allow to combine on the same nanodevice not only therapeutic agents linked to the Au shell, but also different contrast agents for PET and MRI analysis 64 such as the Cu isotope, dispersed into Cu shell, and the superparamagnetic core of Fe3O4. The MNPs obtained had been characterized by different physico-chemical techniques (XRPD, VSM, AFM and TEM) to study their properties. Subsequently MNPs had been coated with Poly-L-lysine that contributes to improve the NPs dispersion into polar solvents, the cellular uptake and allows the further functionalization with MTX and FA. Furthermore, to collect confocal fluorescence microcopy images of these nanosystems internalized into cells, we labeled the residues of Lys with the fluorescent probes (Texas Red, FITC). Afterwards we incubated engineered nanoparticles with human granulocytes in order to investigate their internalization and the possible adverse effects of MNPs on cells viability. Experimental evidence of granulocytes engulfment had been collected by SEM and fluorescence microscopy of the cellular samples, before and after incubation with the activated nanoparticles. After incubation not evident adverse effect on cells were revealed. Both SEM and fluorescence microscopy images confirmed the phagocytosis of MNPs, the former by the EDX analysis and the later by collecting by the Z-stack modality images. Taking advantage of the physiological function of granulocytes, their great mobility in blood flow that leads to a detectable presence also in tumoral tissues, we hypothesize to exploit the same cells as

carrier of our functionalized nanoparticles, avoiding the possible aggregation of MNPs in the physiological medium, the formation of the protein corona and the capture by the reservoir organs. References [1] Liberatore M., Barteri M., Megna V., D’Elia P., Rebonato S., Latini A., De Angelis F., Scaramuzzo F. A., De Stefano M. E., Guadagno N. A., Chondrogiannis S., Maffione A. M., Rubello D., Pala A., Colletti P. M., Clin. Nucl. Med. 4, (2015) e104-e110 [2] L. Vigderman, E. R. Zubarev, Adv. Drug Deliv Rev, 65, (2013), 663–676 [3] Arnida,. Janát-Amsbury M.M, Ray A., Peterson C.M., Ghandehari H., Eur. J. Pharm. Biopharm., 77, (2011) 417–423 [4] Schaffler M., Semmler-Behnke M., Sarioglu H., Takenaka S., Carsten Schleh A. W., Hauck S. M., Johnston B. D., Kreyling W. G., Nanotechnology 24, (2013), 265103-265112 [5] Choi Mi-Ran, Katie Stanton-Maxey J., Stanley J. K., Levin C. S., Bardhan R., Akin D., Badve S., Sturgis J., Robinson J. P., Bashir R., Halas N. J., Clare S. E., Nano Lett., 7, (2007), 3759-3765 [6] Passeri D., Dong C., Reggente M., Barteri M., Scaramuzzo F. A., De Angelis F., Marinelli F., Antonelli F., Rinaldi F., Marianecci C., Carafa M., Sorbo A., Sordi D., I. Arends. W.C.E, Rossi M., Biomatter, 40, (2014),1-16

Folic Acid or Methotrexate Lipoic Acid

Poli-L-Lysine

Texas Red

Figure 1: schematic representation of core shell MNPs engineered with folic acid or methotrexate

Automated patterning of Nanocarbons inks using magnetic Micro Contact printing a,b,c

a,b,d

a,b

Aude Delagarde , Lin Yang , Jean-Christophe Cau , Emmanuel Flahaut , Christophe Vieu a CNRS, LAAS, 7 avenue du colonel Roche, F-31400 Toulouse, France b CNRS, Institut Carnot Cirimat, F-31062 Toulouse, France c Univ de Toulouse, INP, LAAS, F-31400 Toulouse, France d Univ de Toulouse, UPS, LAAS, F-31400 Toulouse, France e Univ de Toulouse, INSA, LAAS, F-31400 Toulouse, France f Innopsys, F-3190 Carbonne, France aude.delagarde@laas.fr, j-cau@innopsys.fr

a,e

Nanocarbon micropattern integration into sensing devices is a key technology for various applicative fields in flexible electronics and wearable sensors. In this paper, we demonstrate that an automated micro contact printing (µCP) process can be implemented on a commercial system to generate nanocarbons (few layer graphene and carbon nanotubes) micropatterns. Basically, µCP consists in the use of a micro-patterned polydimethylsiloxane (PDMS) stamp, which is inked by the molecules of interest. This inked and dried PDMS stamp is then gently brought into contact with a substrate and transfer patterns of the molecules of the ink adsorbed at the stamp surface. The conventional inking method for µCP consists in incubation of the inking solution onto the PDMS stamp [1]. When such a method is employed for nanocarbon containing inks, the resulting patterns exhibit severe defects related to the poor homogeneity of the nanocarbon film adsorbed at the stamp surface. To improve the printing process of nanocarbon inks, we have previously proposed to ink the PDMS stamp by spray coating an aqueous suspension of nanocarbons materials on an activated hydrophilic micro-patterned PDMS stamps (Figure A, 1) [2]. In this paper we extend this methodology by demonstrating that it can be implemented at an industrial level, using an automated printing tool (Innostamp40) which combines inking by spray coating and solvent and temperature assisted transfer printing using magnetically manipulated PDMS stamps [3]. Aqueous nanocarbons inks were prepared either with few layers graphene (FLG), or carbon nanotubes (CNTs) and carboxymethyl cellulose was added to improve the dispersion and stabilize the inks. After inking a magnetic stamp by spray coating, we performed µCP with solvent (Ethanol) mediation using an automated micro-contact printer: the Innostamp40 (Figure A, 2 left). The automated head, which contains magnets, was programmed to pick up an inked magnetic PDMS stamp, dispense a controlled volume of solvent (22 µL) on the receiving substrate, align the stamp, contact the surface and release the stamp. The substrate was heated (45 to 90°C) during 10 to 20 min in order to improve the transfer. Using the Innostamp40 for µCP with solvent mediation, we managed to generate at low cost reproducible micropatterns of FLG and CNTs ( Figure B) with a good alignment and on a wide range of substrates, including flexible ones. The whole process and the results will be detailed during the conference. References [1] J. L. Wilbur, A. Kumar, E. Kim, and G. M. Whitesides, Adv. Mater., vol. 6, no. 7–8, (1994) 600–604. [2] A. Béduer, F. Seichepine, E. Flahaut, and C. Vieu, Microelectron. Eng., vol. 97 (2012) 301–305. [3] J.-C. Cau, L. Lafforgue, M. Nogues, A. Lagraulet, and V. Paveau, Microelectron. Eng., vol. 110 (2013) 207–214. 8"#9/ : ,/ 2##’ ;#) #4<+.’ 04,6,-#=>? @ #5&) ( 0#A<#50.) <#-’ ) 1/ 2# B<+.’ 04,6,-# =>? @ #5&) ( 0#

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Figure A: Scheme of 1) the process of spray coating using an airbrush system, 2) on the left: pictures of an Innostamp 40, on the right: process for automated micro contact printing with solvent mediation.

Figure B: SEM pictures of CNTs thin films pattern on a glass slide, printed by Innostamp40.

Characterization of the effect of humidity on nanoparticle based strain gauges using small angle x-ray scattering coupled with electromechanical measurements 1

Lucas Digianantonio, Mélanie Gauvin, Thomas Alnasser, David Babonneau, Alessandro Coati, 1 1 1 1 Benoit Viallet, Jérémie Grisolia, Guillaume Viau and Laurence Ressier

1 LPCNO, INSA-CNRS-UPS, 135 avenue de Rangueil, 31077 Toulouse, France 2 Institut P', CNRS - Université de Poitiers, 11 Boulevard Marie et Pierre Curie, 86962 Futuroscope Chasseneuil, France 3 Synchrotron Soleil, L'Orme des Merisiers Saint-Aubin, 91192 Gif-sur-Yvette, France laurence.ressier@insa-toulouse.fr Abstract In the last past years, our group has developed resistive nanoparticle based strain gauges made of an assembly of colloidal gold nanoparticles deposited on a flexible polyimide substrate by convective selfassembly [1,2,3]. The nanoparticles are coated with organic ligands, thereby the current flow in the nanoparticle assembly is driven by the tunnel conduction between neighboring nanoparticles through the ligand barriers. This leads to an exponential increase of the electrical resistance of these gauges when a strain is applied to the substrate, conferring them a very high sensitivity (30 times the sensitivity of a conventional metallic strain gauge). Moreover, these nanosensors present a very low electrical consumption because of their high resistance at rest (adjustable between 10kȍ DQG 0ȍ and an ease of integration due to the small size of their active area (<0.1mm²). Despite all these advantages, nanoparticle based strain gauges present one main issue: their sensitivity to humidity: when the humidity varies from 10 to 60%, the electrical resistance at rest of the gauges increases of 40% and their sensitivity of 35%. We have thus investigated the impact of humidity on the strain gauges using small angle x-ray scattering (SAXS) measurements, conducted at the Soleil synchrotron on the SIXS beamline [4]. The samples were placed in a climatic chamber and the SAXS measurements were coupled with electrical ones (Figure 1), to correlate the evolution of the inter-particle distance at the nanoscale with the increase of the electrical resistance observed at the macroscopic scale. As the humidity increases, these experiments revealed an increase of the inter-particle distance which is in good agreement with the increase of the electrical resistance, this coupled with a reorganization of the nanoparticles. Eventually in order to protect the strain gauges from the effect of the humidity we have developed an encapsulation solution based on the deposition of Al2O3 by atomic layer deposition. References [1] C. Farcau, N.M. Sangeetha, H. Moreira, B. Viallet, J. Grisolia, D. Ciuculescu-Pradines & L. Ressier, ACS Nano, 5 (2011) 7137 [2] N.M. Sangeetha, N. Decorde, B. Viallet, G. Viau & L. Ressier, J. Phys. Chem. C, 117 (2013) 19351940 [3] H. Moreira, J. Grisolia, N. M. Sangeetha, N. Decorde, C. Farcau, B. Viallet, K. Chen, G. Viau and L. Ressier, Nanotechnology, 24 (2013) 095701 [4] N. Decorde, N. M. Sangeetha, B. Viallet, G. Viau, J. Grisolia, A. Coati, A. Vlad, Y. Garreau & L. Ressier, Nanoscale, 6 (2014) 15107 Figure 1

a) Schematics of the experimental setup used to characterize the effect of humidity on the nanoparticle based strain gauges with small angle x-ray scattering, b) Typical SAXS scattering pattern of an unstrained gauge at a humidity of 30%

Interface study of graphene on AlGaN/GaN heterostructures using Raman Spectroscopy Srujana Dusari, Nitin Goyal, Martin Debiasio, Andreas Kenda Carinthian Tech Research AG, Europastrasse 4/1, 9524 Villach, Austria Srujana.Dusari@ctr.at Graphene has attracted much attention due to its unique physical properties, such as high carrier mobility and high saturation velocity, which make it promising candidate for high speed devices and circuits [1]. On the other hand, GaN has been widely studied for high voltage and high power switching applications, due to its high temperature operation and high efficiency. Interfacing AlGaN and GaN causes polarization due to lattice mismatch and forms two-dimensional electron gas [2]. AlGaN/GaN is an attractive structure for the design of sensor components that can operate in harsh environments. It has been shown that by integrating unique characteristics of these two materials could lead to interesting results like Ohmic contact formation between metal and semiconductor [3], heat spreaders for GaN transistors [4], transparent conducting layers for GaN LEDs and ultraviolet and visible photodetectors [5]. Here, we investigate the interface properties of graphene on AlGaN/GaN heterostructures using Raman spectroscopy.

References [1] K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, Y. Zhang, S. V. Dubonos, I. V. Grigorieva, A. A. Firsov. (2004): Electric Field Effect in Atomically Thin Carbon Films, Science. 306(5696): 666â&#x20AC;&#x201C;669.[2] O. Ambacher, J. Smart, J. R. Shealy, N. G. Weimann, K. Chu, M. Murphy, W. J. Schaff, and L. F. Eastman. (1999): Two-dimensional electron gases induced by spontaneous and piezoelectric polarization charges in N- and Ga-face AlGaN/GaN heterostructures. J. Appl. Phys. 85, No. 6, 3222.[3] P. S. Park, K. M. Reddy, D. N. Nath, Z. Yang, N. P. Padture and S. Rajan (2013): Ohmic contact formation between metal and AlGaN/GaN heterostructure via graphene insertion. Appl. Phys. Lett. 102, 153501. [4] Z. Yan, G. Liu, J. M. Khan & A. A. Balandin (2012): Graphene quilts for thermal management of highpower GaN transistors. Nature Comm. 3:827. [5] F. Lin, S-W. Chen, J. Meng, G. Tse, X-W. Fu, F-J. Xu, B. Shen, Z-M. Liao, and D-P. Yu (2014): Graphene/GaN diodes for ultraviolet and visible photodetectors. Appl. Phys. Lett. 105, 073103.

Functional ZrO2 nanoparticles as lubricant additives.

Jorge Espina Casado, Humberto Rodríguez-Solla, Antolin Hernández Battez, Rosana Badía Laíño, Marta Elena Díaz García Department of Physical and Analytical Chemistry, University of Oviedo, Av. Julián Clavería 8 33006, Oviedo, Spain medg@uniovi.es Abstract In the last decade considerable effort has been devoted to the development of organic-inorganic hybrid lubricants by introduction of different kind of nanoparticles within the base oil. When nanoparticles are added in small concentration a significantly improved performance of the base oil is observed: reduction of interfacial friction and improvement of the load-bearing capacity of the parts [1-4]. However, when using raw nanoparticles there are some withdraws that limit any benefit. Due to their high surface energy, nanoparticles tend to aggregate and sediment. Some of disadvantages can be solved or minimized by surface functionalization of the nanoparticles. In fact, it has been demonstrated that surface grafting of nanoparticles using amphiphilic organic chains is an effective way to get stable dispersions and strengthen the tribological properties of the oil. In this work, we describe the functionalization of ZrO 2 nanoparticles with three different longchain hydrocarbons, octanoyl-, decanoyl- and palmitoyl chlorides. The reaction between nanoparticles and the different organic chlorides was performed in dichloromethane under inert atmosphere (N2). The synthetized functional nanoparticles were characterized by TEM, FTIR spectroscopy, RMN and Thermogravimetric analysis. The nanoparticles were dispersed in a lubricant base oil using an ultrasonic probe. The different factors affecting the sonication process were studied using a two level experimental design measuring the size or presence of agglomerates by dynamic light scattering. The stability was measured using a Turbiscan AGS equipment. The variation of the backscattering and the transmission with time are a measure of the stability of the suspension. In Figure 1, we can observe that, after 24 h, the backscattering variation at the top and at the bottom of the measurement cell were lesser for decanoyl grafted ZrO2 nanoparticles than for the raw ones. The tribological properties of the functional and non-functional ZrO2 nanoparticles were measured and the results in Figure 2 showed a significant improvement using not only the raw ZrO2 nanoparticles as additive but also with functional ZrO2, with better results in the latter case. These results are highly promising and work aimed to use these functional nanoparticles as lubricant additives for industrial applications is currently in progress. References [1] Da Jiao et al, Applied Surface Science 257, The tribology properties of alumina/silica composite nanoparticles as lubricant additives (2011) 5720-5725 [2] Zhang M et al, Tribol. Int 42, Performance and anti-wear mechanism of CaCO3 nanoparticles as a green additive in poly-alpha-olefin (2009) 1029-1039 [3] C. Shahar et al, Langmuir 26, Surface functionalization of WS2 Fullerene-like nanoparticle (2010) 4409-4414

[4] D. Kim and L.A. Archer, Langmuir 27, Nanoscale organic-inorganic hybrid lubricants (2011) 3083-3094

Figures

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ZrO2

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Figure 1: 24 hours backscattering variation at the top and the bottom of the measurement cell

Figure 2: Friction coefficient with a 0,5% concentration of nanoparticles (Standard four ball assay, ASTM 4172-94)

Preparation and characterization of Pd-NPs doped UO2 samples: nanotechnology approaches to evaluate the behavior of spent nuclear fuel in deep geological repositories. Alexandra Espriu*, Julio Bastos-Arrieta, Joan de Pablo and Ignasi Casas. Departament d’Enginyeria Química, Universitat Politècnica de Catalunya (UPC), Av. Diagonal 647, 08028 Barcelona, Spain alexandra.espriu@upc.edu Abstract To assess the safety of the hypothetical future deep geological repository (DGR) of Spent Nuclear Fuel (SNF), several studies have been centered in the SNF behavior in contact with groundwater. The SNF contains transuranium elements as well as fission products, such as I, Sr, Cs, Mo, etc. Some of the fission products (i.e., Pd, Pt, Rh…) are found in metallic form as epsilon particles. Besides, due to radiolysis, oxidizing species are expected to be formed in the near field of the SNF and they could oxidize the SNF matrix to more soluble U(VI) solid phases. Nevertheless, İ-particles could prevent this oxidation and, therefore, protect the SNF[1]. The most conservative projections consider that it may take 1000 years until water comes into contact with the fuel. At this situation there might be a series of steps or reactions between the SNF and water (water radiolysis, fuel oxidation, fuel dissolution and precipitation of secondary phases). Each stage will be influenced by a series of parameters such as pH, temperature, composition of water and pressure. Specifically, water radiolysis will result in both oxidant (H2O2, O2) and reducing (H2) species. However, the main presence of hydrogen is expected to come from the anoxic corrosion of the steel canisters containing the SNF. [2–5] In this communication we present the application of Pd-NPs to the preparation of doped UO2 samples, in order to simulate the presence of H-particles into SNF. For Pd-NPs, the advantages of nanometric scale are reflected as enhanced catalytic activity and gas storage[6]. Advanced Electron Microscopy and X-Ray Photoelectron Spectroscopy (XPS) characterization are presented in order to stablish the influence of the presence of Pd-NPs on the oxidation processes of UO2 under representative DGR conditions. References [1] A. Martínez-Torrents, S. Meca, N. Baumann, V. Martí, J. Giménez, J. De Pablo, I. Casas, Polyhedron 55 (2013) 92. [2] J.S. Goldik, J.J. Noël, D.W. Shoesmith, Electrochim. Acta 51 (2006) 3278. [3] S. Sunder, N.H. Miller, D.W. Shoesmith, Corros. Sci. 46 (2004) 1095. [4] M. Razdan, D.W. Shoesmith, Faraday Discuss. 00 (2015) 1. [5] D.W. Shoesmith, J. Nucl. Mater. 282 (2000) 1. [6] J.M. Campelo, D. Luna, R. Luque, J.M. Marinas, A. a Romero, ChemSusChem 2 (2009) 18. Figures

Figure 1: Stages for the evaluation of the effect of Pd-NPs over the oxidation of uranium oxide in DGR

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Photoresponsive Bridged Silsesquioxane Nanoparticles with Tunable Morphology for Light-Triggered Plasmid DNA Delivery Y. Fatieiev, J. G. Croissant, S. Alsaiari, B. A. Moosa, D. H. Anjum and N. M. Khashab King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia yevhen.fatieiev@kaust.edu.sa, niveen.khashab@kaust.edu.sa Bridged silsesquioxane (BS) nanomaterials with chemical structures O 1.5Si-R-SiO1.5 with organic R 1 groups are emerging as the next generation of organosilica nanocomposites. Consequently, the BS matrix photophysical, chemical, thermal and mechanical properties can be governed by the nature of 2 homogenously distributed organic fragments within the siloxane network. Nonetheless, due to the synthetic challenge to control the kinetic in sol-gel processes, most non-porous BS materials that have 3 been extensively studied in the past two decades were macroscaled. Ideally, for biomedical purposes BS NPs should be non-aggregated sub-200 nm nanomaterials to benefit the enhanced permeation and retention (EPR) effect and, thus, accumulate in cancerous tissues and organs. Photoresponsive bridged alkoxysilane precursor was used to synthesize nanomaterials (sub-200 nm) with tunable size and morphology, affording non-aggregated dense or hollow nanospheres. The organic-inorganic nanomaterials possessed a very high organic content (50%) of photoresponsive fragments which enabled the on-demand charge reversal from positive (+46 mV) to negative (-39 mV) values. Furthermore, this feature was harnessed to apply BS nanocarriers without further functionalization for the first time for light-triggered plasmid DNA delivery in cancer cells. The lightactuation was found to be effectively delivering DNA while the non-irradiated nanomaterials did not induce significant gene expressions (Figure 1). Dye-doped hollow BS NPs are envisioned for biomedical imaging while the use of a near-infrared fluorophore could extend its potential for in-vivo biomedical applications. References [1] J. Croissant, X. CattoĂŤn, M. Wong Chi Man, A. Gallud, L. Raehm, M. Maynadier, J.-O. Durand, Adv. Mater., 26 (2014), 6174. [2] L.-C. Hu, K. J. Shea, Chem. Soc. Rev., 40 (2011), 688. [3] G. Creff, B. P. Pichon, C. Blanc, D. Maurin, J.-L. Sauvajol, C. Carcel, J. J. E. Moreau, P. Roy, J. R. Bartlett, M. Wong Chi Man, J.-L. Bantignies, Langmuir, 29 (2013), 5581. Figure 1. CLSM images on HeLa cells incubated with BS NPs binding DNA strands after 6 h of incubation. DNA is tracked via GFP fluorescing in green after translation in the nuclei, thus proving the DNA delivery from BS NPs. Scale bars of 40 Îźm.

An analysis tool for decision making support on nanomaterials applications - a preliminary case study Barbara Gabriel, Victor Neto Centre for Mechanical Technology and Automation, Department of Mechanical Engineering University of Aveiro, 3810-193 Aveiro, Portugal Aveiro Nanotechnology Institute, University of Aveiro, 3810-193 Aveiro, Portugal barbara.gabriel@ua.pt Abstract The relevance of nanotechnology for innovation is a reality scientifically well documented [1]. Despite this fact, its effective and practical application is still a challenge that must be assumed in order to define guidelines of intervention to a deep collaboration between stakeholders. Being so relevant, the university and business effective collaboration for (in)novation, competitiveness and personal enrichment, several steps must be followed (or reinforced) in a hierarchical intervention, in which all the agents must be aware of their role. However, considering that the physical infrastructures, for that purpose, already exist, such as incubators, competitiveness and transfer knowledge units, the main question remains: Are the actors really communicating and, consequently, committed? That's the biggest challenge: The need for a social change in order to overcome the current obstacles: distinct HQWLWLHV G\QDPLFV DQG ÂłODQJXDJHVÂ´ EHWZHHQ VWDNHKROGHUV DV ZHOO DV UHVSRQVHV IHHGEDFN WR VRFLHW\ demands. Consequently, the gap in communication (mostly regarding quality) must be narrowed to pursuit the excellence in R&D, in universities curricula and the effective dissemination and final application at the industry. The work developed, based on preliminary study cases, intends to provide a tool to assist the narrowing of the gap that still exists between R&D in research centres/universities and its application at industry, by means of providing a common language translated in to the development of an index that expresses and measures the usability of a trinity of nanomaterials/production technology/product Âą developed in universities and research centres Âą LQWR WKH EXVLQHVV HQYLURQPHQW FRQVLGHULQJ ERWK VWDNHKROGHUVÂś demands. Therefore, the major outcome intends to be a contribution to improve the industry competitiveness and economic growth through the innovation process. For that purpose, the development of a tool Âą NTU (Nano-Technology-Usability) index Âą as illustrated in Figure 1, gathering the information based on TRL index, HSSE issues, economic viability considering the research conducted in universities and research centres but also, and with the same relevance, the industry sector demands and trends is proposed 7KH 178 LQGH[ LQWHQGV WR GHILQH D FRPPRQ ÂłODQJXDJHÂ´ WKDW allow stakeholders to communicate in a more efficient and effective way and, more important, to take advantage of the competencies and knowledge from both sides. References [1] P. Queipo, D. Gonzalez, A. Reinhardt, T. Zadrozny, M. Cioffi, A. Bianchin and P. Matteazzi, Sustainable Development, Knowledge Society and Smart Future Manufacturing Technologies World Sustainability Series 2015, 73-79 Figures Figure 1: NTU index schematic

Magneto-photoluminescence spectroscopy of bright and dark excitons in isolated semiconducting single-walled carbon nanotubes 1*

Morgane Gandil , Kazunari Matsuda , Philippe Tamarat & Brahim Lounis 1

LP2N, Univ. Bordeaux - CNRS - Institut d'Optique Graduate School, F-33400 Talence, France 2 Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan * morgane.gandil@institutoptique.fr

Abstract Since the first experimental evidence of photoluminescence of semiconducting single-walled carbon nanotubes (SWNTs) [1], studies have been conducted to investigate the optical properties of these nano-structures, motivated by possible applications in the fields of quantum information, biological labeling, opto-electronics or laser technology. The unidimensional nature of SWNTs, through the combined effect of the strong spatial confinement and the low coulomb screening, leads to high electron-hole binding energies [1,2]. The photo-excitation of SWNTs results therefore in the formation of strongly correlated electron-hole pairs, so-called excitons, which dominate the photo-physical behavior of these nano-objects. Due to the configuration of the excitonic band structure, the luminescence of semiconducting SWNTs is mainly governed by the two lowest singlet states: the upper one is optically active (bright) whereas the lower one corresponds to a parity forbidden dipole transition (dark). A magnetic field applied along the SWNT axis induces the coupling of these two levels through the Aharonov-Bohm effect. The resultant magnetic brightening of the dark state opened up the field of magneto-photoluminescence spectroscopy [3,4] as a promising way to investigate the photo-physical properties of SWNTs. Here, we report the study of isolated CVD-grown SWNTs suspended on lithographed trenches of a silicon substrate. Measurements were performed at the single-object level using a home-built confocal optical microscope with a large numerical aperture (NA = 0.95) operating at cryogenic temperatures (down to 2K) and high magnetic field (up to 7T). Photoluminescence spectra and decays of single SWNTs were acquired under various experimental conditions, including different magnetic fields, temperatures and optical excitation frequencies. As displayed in the figure, the dark state spectacularly brightens with increasing magnetic fields, which reveals the dark/bright energy splitting. From the spectroscopic and time-resolved measurements, relaxation dynamics of the bright and dark excitons and their interactions with the phonons will be discussed. Figure 7 6

Magnetic field (T)

Dark 5 4 3

Bright

2 1 0 1.28

1.285

1.29

1.295

1.3 Energy (eV)

1.305

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Photoluminescence spectra of a single (6,5) SWNT resonantly excited on its S22 transition with a 561nm CW laser under various magnetic fields.

References [1] Wang, F., Dukovic, G., Brus, L. E., & Heinz, T. F., Science, 5723 (2005) 838Â±41. [2] 0DXOW]VFK - 3RPUDHQNH 5 5HLFK 6 &KDQJ ( 3UH]]L ' 5XLQL D Â« /LHQDX & , Physical Review B, 24 (2005) 241402. [3] Shaver, J., & Kono, J., Laser & Photonics Review, 3 (2007) 260Â±274. [4] Matsunaga, R., Miyauchi, Y., Matsuda, K., & Kanemitsu, Y., Physical Review B, 11 (2009) 115436.

Influence of SiC substrate modification on the growth of epitaxial graphene A. GarcĂa-GarcĂa1,2, A. Ballestar2,3, P. Godignon1, J. M. de Teresa3,4,5,6, R. Ibarra3,4,6 E-mail: alberto@gpnt.es 1 CNM-IMB-CSIC,

Campus UAB, Bellaterra, 08193 Barcelona, Spain Nanotech, S.L., Miguel Villanueva 3, 26001 LogroĂąo, Spain 3 LMA, INA, Universidad de Zaragoza, 50018 Zaragoza, Spain 4 Departamento de FĂsica de la Materia Condensada, Universidad de Zaragoza, 50009 Zaragoza, Spain 5 ICMA, Universidad de Zaragoza, 50009 =DUDJR]D 6SDLQ Ě§ 6 TALEM, CEMES-INA, CNRS-Universidad de Zaragoza, Toulouse, France 2 Graphene

Since the isolation of graphene in 2004 [1], the growth of research and applied technologies based on this material is exponential. To make these technologies accessible to an industrial level a systematic fabrication process, which makes production affordable, is highly demanded. The epitaxial growth of graphene on Silicon Carbide (SiC) by thermal sublimation is one the leading techniques for such aim [2, 3, 4], however the improvement of the quality of the graphene layer remains as a challenge. The use of CMOS compatible substrates improves the overall fabrication process of electronic devices, as graphene is from the beginning included in the supporting material. Moreover, the use of SiC allows us to effectively proceed with doping, implantation, or micro-structuring as required. Therefore, different steps of the production can be skipped, such as lithography and patterning, avoiding potential contamination and damages on the graphene layer. We systematically grew epitaxial graphene on 6H-SiC on and off axis substrates, in which we slightly modified their intrinsic properties. Such modifications were controlled via nitrogen implantation and doping processes. We investigated the quality and properties of the prepared samples by means of Optical and Atonic Force Microscopy (AFM), as well as Raman Spectroscopy. Microstructural properties are correlated with Raman spectroscopy results. [1] K. S. Novoselov et al., Science 306 (2004) 666. [2] S. Hertel et al., Nature Communication 3 (2012) 957. [3] K. V. Emtsev et al., Nature Materials 8 (2009) 203. [4] C. Virojanadara et al., Physical Review B 78 (2008) 1.

Fig. 1: (a) AFM topography image of the surface of one of the investigated samples. (b) AFM phase of the highlighted area in (a). (c) Raman spectrum obtained at different points of one sample, as indicated in the optical image shown in (d).

Chemical synthesis of FeCo nanoparticles: size and shape control. 1

C. Garnero , C. Garcia-Marcelot , L.-M. Lacroix , K. Soulantika , P. Fau , B. Chaudret

1 UniversitĂŠ de Toulouse, LPCNO, UMR 5215 INSA-CNRS-UPS, 135 av. de Rangueil 31077 Toulouse 2 Lab. Chimie de Coordination, UPR 8241, 205 route de Narbonne, 31077 Toulouse garnero@insa-toulouse.fr Soft magnetic nanoparticles (NPs) and their synthesis have been extensively studied over the past decades due to their unique properties. Among them, FeCo alloy presents a very high saturation 4 3 magnetization (Ms = 240 emu/gFeCo) with a low anisotropy constant (K Fe50Co50 = 1,5.10 J/m ). These characteristics make FeCo NPs a very promising material for various applications such as 1 2 hyperthermia and nanoelectronics . However, the chemical synthesis of FeCo NPs remains a challenge. Indeed, the obtained FeCo NPs are often not well crystallized or have a core-shell structure, resulting in low saturation magnetization (Ms). The desired bulk magnetic properties is generally 3,4 achieved after an annealing process , but after such a treatment the NPs are aggregated and are no more dispersible. Another challenge is the fine tuning the size and the shape of the FeCo NPs, since these two parameters are controlling the magnetic properties and thus the specific absorption rate for hyperthermia treatments. We managed to obtain homogeneous FeCo NPs through a new chemical synthesis based on co-decomposition of an iron and a cobalt metalloid amide ({X[N(SiMe3)]2}2 (X = Fe or Co)) under 3 bars of H2 at 150Â°C in presence of organic ligands. The size and shape of the nanoparticles can be controlled by adjusting the concentration of the ligands and their nature, while the FeCo atomic composition can be tuned by adjusting the precursors ratio. For example, cubes of 8 nm can be obtained by using 3 equivalents of palmitic acid while spheres of 11 nm can be obtained with 3 equivalents of hexadecylamonium chloride (Figure 1). The obtained NPs are well crystallized and exhibit magnetic properties close to the bulk ones (Figure 2). At the end we have access to a large panel of FeCo NPs that can be tested in hyperthermia measurements. Figures a)

Figure 1: TEM images a) cubes synthesized with palmitic acid b) spheres of synthesized with hexadecylamonium chloride a)

b) b)

Figure 2: a) High resolution transmission electron microscopy image of an 8 nm cube, b) Energy dispersive X-ray mapping of 8 nm spheres, (green for cobalt and red for iron) References [1] Lacroix, L.-M.; Malaki, R. B.; Carrey, J.; Lachaize, S.; Respaud, M.; Goya, G. F.; Chaudret, B. J. Appl. Phys. 2009, 105 (2), 023911. [2] Han, Z.; Li, D.; Wang, H.; Liu, X. G.; Li, J.; Geng, D. Y.; Zhang, Z. D. Appl. Phys. Lett. 2009, 95 (2), 023114. [3] Desvaux, C.; Lecante, P.; Respaud, M.; Chaudret, B. J. Mater. Chem. 2010, 20 (1), 103. [4] Wang, C.; Peng, S.; Lacroix, L.-M.; Sun, S. Nano Res. 2009, 2 (5), 380.

Nanofabrication of silicon nitride photonic crystals membranes Valentim, P. T.,1, 2, 3 Vasco, J. P.,2, 3 Fonseca, H.,1 Borme, J.,1 Assis, P.-L.,2, 3 Rodrigues, W. N.,2, 3 Quivy, A. A.,3, 4 Guimarães, P. S. S.,2, 3 Gaspar, J.1 1INL-

International Iberian Nanotechnology Laboratory, Braga, Portugal de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil 3DISSE-INCT de Nanodispositivos Semicondutores, Brazil 4Instituto de Física da Universidade de São Paulo, CP 66318, 05314-970 São Paulo, SP, Brazil pablo.valentim@visitor.inl.int 2Departamento

We report on the nanofabrication of silicon nitride (SiNx) L3 photonic crystals nanocavities with high geometrical quality. Lately, these kind of devices have attracted much attention due to their capability for confining, guiding and modifying the light transportation within the matter. These can also interact with novel materials such as transition metal dichalcogenides (TMDC) and antibodies within the visible range of the electromagnetic spectrum [1]. The aim of this work is to develop an efficient fabrication process and study the emission properties of such cavities both with photoluminescence and reflectivity experiments at room temperature. Theoretical calculations were carried out using guided mode expansion approach to help us establish the optimal geometrical parameters of our structures, such as lattice parameter (a), radius (r) and thickness (t), which in our case, were chosen to be a = 270 nm, r = 83.7 nm and t = 270 nm, respectively. Taking into account the refractive index for SiNx (n = 2.01), the theoretical fundamental L3 photonic mode is expected to be around 672 nm and has a theoretical quality factor (Q) of 4300. Figure 1 bellow shows the schematics of our structure. It is known from literature that fabrication imperfections are the major causes for cavities low quality factors [2]. To overcome these challenges, we have developed a method for producing high quality factor cavities using MEMS/NEMS fabrication based technologies. Firstly, using a plasma enhanced chemical vapor deposition (PECVD) system, we deposit a 270-nm-thick layer of SiNx on the front side of a 725 µm-thick double side polished (DSP) silicon wafer. A 3500-nm-thick layer of silicon dioxide (SiO2) is then deposited on the backside. The photonic crystal cavity (PHC) pattern is produced on the front side of the wafer by the means of a negative tone resist E-beam lithography, development and deposition 25 nm-thick layer of Al followed by lift-off in a Microstrip solution at 60°C under ultrasonic agitation. By the end of this step we have fabricated a metallic aluminum hard mask that will be used to transfer the PHC pattern into the SiNx layer. After that, the sample is etched in a fluorine based reactive ion etch (RIE) process to remove only the areas on the SiNx layer that are not protected by the Al mask. Then, on the back side of the wafer, a conventional optical lithography is combined with a RIE plasma to make small apertures on the SiO2 layer that will serve as a hard mask for deep reactive ion etch (DRIE) of silicon. During this process most of Si is removed, leaving just a 100 µm-thick layer left. The last step is an anisotropic Tetramethylammonium hydroxide (TMAH) wet etch. Along this part, the last 100 µm of Si are slowly etched, in a rate of 45 µm/h, enabling the gentle releasing of the patterned SiNx suspended membranes. The outcome are free-standing silicon nitride layers exhibiting very good holes circularity and very straight side walls, both desirable features of high quality structures necessary to study cavity quantum electrodynamic (cQED) phenomena. We are currently implementing a cross-polarization measurement system that will allow us to perform microphotoluminescence and reflectivity (transmission) experiments at room temperature on the samples. The first objective is to study how the quality factor of these cavities changes with respect to the lattice parameter, hole size and membrane thickness. Afterwards, we intend to investigate the coupling behavior between the cavity mode and external light sources, as well as, the coupling between two photonic cavities containing external light emitters. [1] Gan, X. et al., App. Phys. Letters 103, 181119 (2013); [2] Lim, K-m., et al. Microelectronic Engineering 88, 994-998 (2011).

a) b) c) d) Figure 1: a) Schematic of PHC showing the parameters used in our calculations. To further increase the quality factor five holes on both sides of the cavity, S1, S2, S3, S4 and S5, are displaced outwards by 91 nm, 72.9nm, 23.76 nm, 87.21 nm and 46.71 nm, respectively. b) Theoretical calculation of the fundamental mode electric field distribution. c) PHC pattern after Al deposition. d) PHC structure obtained using the fabrication process described above.

Free-standing self-assembled monolayered nanoparticle membranes and their electromechanical properties by conducting AFM 1

M. Gauvin , T. Alnasser , J. Grisolia , B. Viallet , S. Xie , J. Brugger and L. Ressier * 1

Université de Toulouse, LPCNO, INSA-CNRS-UPS, 135 avenue de Rangueil, Toulouse 31077, France 2 Microsystems Laboratory, Institute of Microengineering, EPFL, 1015 Lausanne, Switzerland *laurence.ressier@insa-toulouse.fr

Abstract Freestanding membranes of dodecanethiol coated 7nm colloidal Au nanoparticles assembled at the liquid/liquid interface [1, 2], are deposited over micrometric holes etched in Si3N4 substrate and addressed by gold electrodes using stencil lithography (Figure 1a). 3)781$ 3HDN )RUFH Tunneling AFM) cartography and spectroscopy are performed on these free-standing self-assembled nanoparticle membranes (Figure 2b). Their deformation cartography and mechanical properties are determined from AFM force-displacement curves measured across the entire membrane area. The Young modulus and pre-stress of these free-standing self-assembled nanoparticle membranes are in the range of several GPa and a few tenth of MPa respectively. Force-dependent current spectroscopy measurements are performed to study intrinsic electro-mechanical properties of monolayered nanoparticle membranes in a substrate-free configuration. On increasing the applied load, we observe an increase in the electrical resistance of the membranes as a result of the membrane deformation. To quantify this effect, the membrane deformation measured by AFM is analyzed using finite element modeling. The electrical resistance variation of the membrane as a function of deformation shows high sensitivity value of ~250. These results show that free-standing self-assembled monolayered nanoparticle membranes are potential candidates for ultra-sensitive nanosensor applications. References [1] K.E. Mueggenburg, X.M. Lin, R.H. Goldsmith, and H.M. Jaeger, Nat Mater, 9, 2007, 656±660 [2] J. He, P. Kanjanaboos, N.L. Frazer, A. Weis, X.M. Lin, and H.M. Jaeger, Small, 13, 2010, 1449±1456

Figure

Figure 1: a) Schematic of free-standing self-assembled monolayered nanoparticle membranes deposited on holey Si3N4 substrate investigated by PFTUNA. Inset shows a scanning electron microscope image of the close-packed nanoparticles in the membrane. b) Typical topography, deformation and current images in PFTUNA mode of a same membrane at a fixed force setpoint of 9 nN and applied voltage of 0.5 V.

Fabrication and analysis of ions diffusive transport through nanoporous ceramic membranes: Influence of pore size, porosity and surface material V. Romero 1, L. Gelde 1, I. Llamas 1, V. Vega 2, J. García 2,3, V.M. Prida 2, B. Hernando 2, J. Benavente 1 1 2 3

Dpto. Física Aplicada I. Facultad de Ciencias, Universidad de Málaga, E-29071 Málaga, Spain. Dpto. Física. Facultad de Ciencias, Universidad de Oviedo, E-33007 Oviedo, Spain. Institut für Angewandte Physik, Universität Hamburg, Jungiusstraβe 11, 20355-Hamburg, Germany

Manufacture of Nanoporous Alumina Membranes (NAMs) by the two step anodization method allows the attainment of well-defined porous structures [1-2]. Moreover, the possible modification of geometrical parameters (pore size and porosity) and membrane surface material by Atomic Layer Deposition (ALD) technique by using different kind of nanoparticles (SiO2, Al2O3, ZrO2,…[3-4]) has increased the range of applicability of these systems. In this work we report the manufacture, geometrical characterization by SEM micrographs and the analysis of the diffusive transport of ions (Cl- and Na+) through the nanopores of different membranes, which is correlated with the porosity/pore radius of the membranes and the material covering their surfaces. This latter analysis was performed by measuring membrane potential with NaCl solutions at different concentrations, which give information on the diffusive flow through the pores and the effect of membrane charge on mass/ion transport. In this context, Donnan exclusion of the co-ions at the solution/membrane interface seem to exert a significant control on the diffusive transport at low NaCl concentrations, while the increase of the electrolyte concentration shows a partial reduction of the electrical effects and the increase of diffusive contribution. [1] H. Masuda, K. Fukuda, Science 268 (1995) 1466-1468. [2] V. Romero, V. Vega, J. García, V.M. Prida, B. Hernando, J. Benavente, J. Colloids Interface Sci. 376 (2012) 40-46. [3] J. Bachmann, R. Zierold, Y.T. Chong, R. Hauert, C. Sturm, R. Schmidt-Grund, B. Rheinländer, M. Grundmann, U. Gösele, K. Nielsch, Angew. Chem. 120 (2008) 6272-6274. [4] V. Romero, V. Vega, J. García, R. Zierold, K. Nielsch, V. M. Prida, B. Hernando, J Benavente, ACS Appl. Mater. Interfaces 5 (2013) 3556-3564 Acknowledgements: To CYCIT, Spain (Project CTQ2011-27770, Feder funds).

Inclusion of silver nanoparticles for improving regenerated cellulose membrane performance L. Gelde (1), M.A. Casado (2), M.I. Vázquez (1), I. Llamas (1), R.J. Contreras (2), J.M. López-Romero (2), J. Benavente (1) (1)

(2)

Departamento de Física Aplicada I. Facultad de Ciencias. Universidad de Málaga. E-29071 Málaga. Spain.

Departamento de Química Orgánica. Facultad de Ciencias. Universidad de Málaga. E-29071 Málaga. Spain.

Cellulose is an important material for membrane manufacture due to its high hydrophilic character, which helps to reduce membrane fouling during solutions separation processes. Moreover, cellulose is the most abundant natural biopolymer forming the basic material in the cell-wall of most plant cells and, consequently, it is considered a promising polymeric resource due its relative low cost [1]. However, the mechanical stability of regenerated cellulose (RC) membranes needs to be improved for filtration applications. In such case, the inclusion of metallic nanoparticles in the structure of the RC membranes may improve their mechanical resistance, but that modification could also affect some other electrochemical transport parameters associated to salt and ions diffusive transport. This paper shows the preparation of silver nanoparticles (AgNPs) and Janus silver nanoparticles (JAgNPs) and their inclusion in the structure of a dense but highly hydrophilic RC membrane by deep coating in water solutions of the corresponding kind of NPs. Silver nanoparticles were obtained by the sodium citrate method already referenced [2], while the Janus character was obtained by immersion interface procedure [3]. Information on elastic, electrical and diffusive properties of the original RC membrane and after nanoparticles modification (RC/AgNPs and RC/JAgNPs, respectively) have been obtained by straightstrength curves and impedance spectroscopy measurements with dry samples, as well as by membrane potential and salt diffusion experiments, being these two latter performed with NaCl solutions at different concentrations [4]. Changes in transport parameters across nanoengineering membranes when compared with the original cellulosic support are analysed; moreover, possible differences in those parameters obtained for RC/AgNPs and RC/JAgNPs membranes were also considered and the results correlated with some nanoparticles characteristics.

[1] D. Klemm, B. Heublein, H.P. Fink, A. Bohn Angewandte Chemie 44(22), (2005) p. 3358. [2] N.R. Jana, X. Peng. J. Am. Chem. Soc. 125 (2003) 14280. [3] V. Sashuk, R. Hołyst , T. Wojciechowski , M. Fiałkowski. J. Colloid Interface Sci. 375 (2012) 180. [4] V. Romero, M .I. Vázquez, J. Benavente. J. Membr. Sci. 433 (2013) 152-159.

Acknowledgements: To CYCIT, Spain (Projects CTQ2011-27770 and CTQ2013-48418, Feder funds).

Magnetic Hyperthermia with Fe@SiO2 Nanoparticles. Synthesis and Efficiency. Arnaud Glaria, Wilfried Solo Ojo, Nicolas Hallali, Julian Carrey, Bruno Chaudret, Sébastien Lachaize, Fabien Delpech, Céline Nayral. Laboratoire de Physique et Chimie des Nano-Objets (LPCNO) - UMR INSA/UPS/CNRS 5215 35 avenue de Rangueil, 31077 Toulouse CEDEX 04, France glaria@insa-toulouse.fr, cnayral@insa-toulouse.fr, fdelpech@insa-toulouse.fr, slachaiz@insa-toulouse.fr Abstract Magnetic hyperthermia is a powerful technique enabling an efficient NPs-mediated treatment of malignant cells either in vitro or in vivo. [1] Major breakthroughs have been reported over the past years but they mainly focused on iron oxide compounds. These materials possess many advantages and can be easily synthesized in aqueous or organic solvents with magnetic properties modulated depending on their size and shape. [2] However, even if these materials show great promises, using pure iron NPs would permit to obtain values of the Specific Absorption Rate (SAR) more than two times larger than the ones obtained with its classical oxide counterparts. [3] The use of these NPs in biological media needs water transfer where one great challenge is to avoid the oxidation of the metal and thus the loss of the magnetic properties. By using a chemical approach, where a non alcoholic media ensures the integrity of the iron NPs during the process, we are able to precisely control the growth of a silica shell as well as the number of iron NPs encapsulated (Figure 1a). [4] This new material already exhibits relatively high values of the SAR in between the ones reported for iron oxide and pure iron NPs respectively (Figure 1b). Moreover, we have developed a simple functionalization method that allows their rapid dispersion in PBS buffer. Finally, we will present how our global synthetic approach will be of great importance for future hyperthermia measurements performed in vitro. References [1] (a) E.-K. Lim, T. Kim, S. Paik, S. Haam, Y.-M. Huh, K. Lee, Chem. Rev., 115 (2015) 327 ; (b) L. H. Reddy, J. L. Arias, J. Nicolas, P. Couvreur, Chem. Rev., 112 (2012) 5818; (c) D. Yoo, J.-H. Lee, T.-H. Shin, J. Cheon, Acc. Chem. Res., 44 (2011) 863. [2] (a) A. Walter, C. Billotey, A. Garofalo, C. Ulhaq-Bouillet, C. Lefèvre, J. Taleb, S. Laurent, L. Vander Elst, R. N. Muller, L. Lartigue, F. Gazeau, D. Felder-Flesch, S. Begin-Colin., Chem. Mater. 26 (2014) 5252 ; (b) C. Martinez-Boubeta, K. Simeonidis, A. Makridis, M. Angelakeris, O. Iglesias, P. Guardia, A. Cabot, L. Yedra, S. Estradé, F. Peiró, Z. Saghi, P. A. Midgley, I. Conde-Leborán, D. Serantes D. Baldomir, Scientific Reports 3 (2013) 1652 [3] B. Mehdaoui, A. Meffre, J. Carrey, S. Lachaize, L.-M. Lacroix, M. Gougeon, B. Chaudret, M. Respaud, Adv. Funct. Mater., 21 (2011), 4573. [4] (a) N. El-Hawi, C. Nayral, F. Delpech, Y. Coppel, A. Cornejo, A. Castel, B. Chaudret, Langmuir, 25 (2009) 7540; (b) F. Delpech, C. Nayral, N. El-Hawi, patent WO 2009071794. Figures 70

1,4 SAR ech25 SAR ech51 SAR ech68 SAR ech81 SAR ech121

1,0

0,8

0,6

0,4

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Fig.1: (a) TEM picture of silica coated iron NPs and (b) their associated hyperthermia measurements, µ0H = 55 mT and f = 50 kHz.

Area (mJ/gFe)

SAR (W/gFe)

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Synthesis of model cobalt catalysts for Fischer Tropsch Synthesis Justine HARMEL

1, 2*

Katerina Soulantika , Philippe Serp , Bruno Chaudret , Adrien Berliet , Antoine 3 3 FĂŠcant , Sylvie Maury

LPCNO, CNRS-UMR5215, INSA Toulouse, Toulouse, France LCC, CNRS-UPR 8241, ENSIACET, UniversitĂŠ de Toulouse, Toulouse, France 3 IFPEN Energies Nouvelles, Solaize, France * harmel@insa-toulouse.fr

Abstract Fischer Tropsch Synthesis is a catalytic process that converts syngas (CO and H2), which can be obtained from the biomass, into hydrocarbons and water. This process attracts a lot of attention as the petroleum resources are decreasing. Even though this process is known since 1923, the reaction mechanism and the deactivation process are still unclear. [1] Cobalt is currently one of the best adapted metals for the catalysis of this reaction since it presents an optimal trade-off between price and catalytic performance The controlled decomposition of an organometallic cobalt precursor in the presence of stabilizing agents and by controlling of the reaction conditions allows the synthesis of size and the shape controlled Co nano-objects in solution. [2] Based on these results we have developed new catalysts elaborated by cobalt overgrowth on preexisting Co nano-particles of a conventional Fischer-Tropsch catalyst. Our method allows the growth of Co nanowires which starts from several sites of the surface of the pre-existing Co nano-particles leading to urchin-like shaped cobalt nano-objects embedded in the porosity of a silica-alumina support. Preliminary results of the catalytic runs with this catalyst present a very high stability. The stability of the catalyst is a very important issue in the case of FTS catalysis, a lot of studies concern the deactivation phenomenon and the origin is still under debate.[3] Another interest of this catalyst is that cobalt nanowires exhibit a hcp crystal structure. According to the literature, for Co FTS catalyst the hcp structure is more active than the fcc one.[4]

References [1] Ivo A. W. Filot et al, Angew. Chem. Int.Ed. 53 (2014) 12746-12750 [2] N. Liakakos et al, JACS. 134 (2012) 17922-17931 [3] M. Claeys et al, ACS Catal. 5 (2015) 841-852 [4] J.-X. Liu et al, JACS 135 (2013) 16284-16287

Figures

TEM picture urchain-shaped cobalt model catalyst for FTS.

Synthesis and characterization of graphene-Ag nanoparticles hybrids Sandra Hernández, M.D. Fernández, M.J. Fernández Departamento de Ciencia y Tecnología de Polímeros. Facultad de Química. Universidad del País Vasco (UPV/EHU). Pº Manuel Lardizábal 3, 20018 San Sebastián. sandra_19_hernandez@hotmail.com Abstract Graphite is a 3D form of carbon with a sheetlike structure. Within each layer, the carbon atoms are arranged in a hexagonal pattern through V bonding involving sp2 hybridization. The layers are held together by weak van der Waals forces. Due to the weak coupling-layered structure, graphite can be intercalated with certain atoms, molecules, and ions to form graphite intercalated compounds. Depending on the intercalated substance, the bonding between the carbon atoms and the intercalate can be covalent or ionic. Grafite oxide (GO) is the typical substance where the bonding is covalent. Graphene sheets can be obtained by chemical reduction of GO. Graphene, a single-layer sheet of sp2hybridized carbon atoms with high surface area and superior mechanical and electrical properties, provides and extraordinary platform for preparing composite nanomaterials [1,2]. Especially, the fabrication of graphene-metal particle nanocomposites is of significant interest due to their potential applications in catalysis, chemical sensing, surface enhanced Raman scattering (SERS), and battery electrodes [3,4]. In this communication, we report the synthesis of graphene-silver nanoparticles hybrids using graphene oxide (GO) in different alkaline environments by a simple one step hydrothermal method in the absence and the presence of an eco-friendly and nontoxic reducing agent, ascorbic acid, at moderate temperatures 40-100ºC. The thermal reduction of graphene oxide in the absence of silver precursor was also studied. The influence of the kind of alkali, NaOH and NH4OH, on the formation of silver nanoparticles (AgNPs) was examined, as well as the presence of the reducing agent. The morphology and structure of the obtained materials were examined by UV-Vis and Raman spectroscopy, FT-IR, XRD, XPS, TEM and thermogravimetric analysis (TGA). The formation of AgNPs on GO sheets was monitored with UV-Vis spectroscopy by measuring the absorbance at definite time intervals at a 400 nm. The spectra showed the formation of nanometer-sized Ag particles and the reduction of the GO sheets. The formation of the AgNPs was indicated by the surface plasmon resonance peak of the AgNPs at around 400 nm. In the absence of reducing agent, the rate of AgNPs formation was faster with NaOH than with ammonia, whereas the presence of ascorbic acid led to a significant increase of the rate of AgNPs formation. The Raman spectra showed that the peak intensities of the D band and G band for the hybrids increased in comparison to the GO, which is attributed to the surface enhanced Raman scattering of AgNPs. The X-ray diffractograms and the XPS spectra of the composites indicated that the AgNPs were composed of pure crystalline silver. The generation of metallic silver nanostructures revealed by UV-Vis absorption spectroscopy, XPS and XRD was confirmed through direct observations by TEM. The graphene sheets were decorated randomly by AgNPs. The nanoparticles showed rounded shapes and different sizes. References [1] [2] [3] [4]

C. Tan, X. Huang and H. Zhang, Materials Today Journal, 16 (2013) 29-36. C.X. Guo, H.B. Yang, Z.M. Sheng, Z.S. Lu, Q.L. Song, C.M. Li, Angew. Chem. Int. Ed. 49, (2010), 3014 ±3017. X. Huang, X. Qi, F. Boey, H. Zhang, Chem. Soc. Rev. 41 (2012) 666±686. X. Huang, Z.Yin, S. Wu, X. Qi, Q. He, Q. Zhang, Q. Yan, F. Boey, H. Zhang, Small, 7, (2011) 1876±1902.

Acknowledgements: We gratefully acknowledge the financial support from Gobierno Vasco (SAIOTEK 2013 S-PE13UN004) and UPV/EHU (UFI11/56), as well as SGIker technical and human support (UPV/EHU).

Neutral and Charged excitons in Tungsten Dichalcogenoides Monolayer a

A.Hichri , S. Jaziri

a,b

Laboratoire de Physique des Matériaux, Faculté des Sciences de Bizerte 7021 Jarzouna, Tunisia. b Laboratoire de physique de la matière condensé, Faculté des sciences de Tunis, Campus universitaire 2092 El Manar, Tunisia.

aida.ezzeddini@gmail.com

Abstract Monolayer transition metal dichalcogenoides (TMDs) have considered as semiconducting alternatives to graphene, for enriching many applications using two dimensional (2D) semiconductors. The principal features of TMDs are a strong Coulomb interaction between electron-hole caused by the relatively large carrier effective masses, reduced screening and carrier confinement. We show that the low binding energies excitonic states deviate strongly for the standard 2D Wannier Mott model due to the correlations with the surrounding dielectric environment. Photoexcited electron hole pairs and doping, induced charges to form trions which are bound states of two electrons with one hole. Using a non-local dielectric screening potential [1], exciton and trion energies calculated for monolayer WS2, in particular, are shown to be in excellent agreement with photoluminescence measurements [2]. According to the mass action law, we calculate the dependence of the intensity of neutral and charged exciton, on doping and temperature. 7KH WULRQ¶V UDGLDWLYH lifetime is found to increase linearly with temperature. Pump-and-probe measurements, clarify the experimental charge transfer mechanism, which is very efficient for exploiting the TMDs for optoelectronic applications.

References [1] Stern, F. and Howard, W., Phys. Rev., 163 (1967) 816. [2] A. A. Mitioglu, P. Plochocka, J. N. Jadczak, W. Escoffier, G. L. J. A. Rikken, L. Kulyuk, and D. K. Maude, Phys. Rev. B, 88 (2013) 245403. Figures Frame 001 ~ 14 Jun 2015 ~

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1.95

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Trion photoluminescence line shape us a function of screening parameter.

CHEMOSYNTHESIZED COPPER NANOPARTICLES: AN EFFECTIVE FUNGICIDAL AGENT AGAINST PLANT FUNGI AVIANSH P. INGLE AND MAHENDRA RAI Department of Biotechnology, Sant Gadge Baba Amravati University, Amravati-444602 (MS), India Email: ingleavinash14@gmail.com

Abstract Nanotechnology is an emerging branch of science, which has potential to solve many problems in different fields including agriculture and part of copper nanoparticles attract biologists because of their significant and broad-spectrum bioactivity. In the present study, we report the chemical synthesis of copper nanoparticles from copper nitrate using CTAB as reducing and stabilizing agent. Initially, the formation of dark purple-violet colour from faint blue colour indicates the synthesis of copper nanoparticles. Primary detection carried out by UV-Vis spectrophotometer analysis showed the absorbance peak at 570 nm which is specific for copper nanoparticles. Further, characterization using Transmission Electron Microscopy confirmed the formation of spherical and square shape nanoparticles in the size range of 6-20 nm. Zeta potential analysis showed that the chemosynthesized copper nanoparticles were comparatively stable having zeta potential of 35 mV. Further, antifungal potential of chemically synthesized copper nanoparticles was evaluated against common plant pathogenic fungi like F. oxysporum, F. moniliforme, F. culmorum, F. tricinctum and Aspergillus niger. The maximum antifungal activity was reported against A. niger followed by F. moniliforme, F. oxysporum, F. tricinctum, whereas the minimum activity was reported against F. culmorum. Similarly, syngergistic effect of these copper nanoparticles was also tested in combination with commercial antifungal agent (ketoconazole), they obtained results proved that the efficacy of the antifungal agent used get enhanced when used in combination with copper nanoparticles. The aim of the present study it to develop novel and effective alternative to the chemical fungicides. In this context from the present study it can be concluded that copper nanoparticles can be used for the development of nanofungicides after extensive studies on its toxicity. Keywords: Chemosynthesis, copper nanoparticles, broad-spectrum bioactivity, plant fungi.

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References 1. Ingle A, Duran N and Rai M. Applied Microbiology and Biotechnology, 98, (2014), pp. 1001-1009. 2. Shende SS, Ingle AP, Gade A, Rai M. World Journal of Microbiology and Biotechnology, 31, (2015), pp. 865-873.

Trends in Mathematical modeling of electrospun Nanofibers Akbar Khodaparast Haghi, Sulmaz Poreskandar, Shima Maghsoodlou University of Guilan, Rasht, Iran akhaghi@yahoo.com Abstract In recent years, with advancing science and nanotechnology, nanofiber production has been a topic of interest to researchers. Advanced nanofiber materials can be used for many applications including: biotechnology, medicine, energy, electronics and environmental filtration. Among the various methods of producing nanofibers, electrospinning is known as an efficient, simple and cost-effective method. Because of electric charge accumulation, the electrospinning jet is diverting from its original paths. This is known as whipping instability. In this article, an advanced form of a model is used to investigate the influences of the effective parameters on whipping instability behavior of electrospinning jet.

References [1] M. Yousefzadeh, M. Latifi, T.M. Amani, W.E. Teo, S. Ramakrishna, Journal of Engineered Fabrics & Fibers (JEFF), , 7 (2) , (2012) 17-23. [2] T. Darsi, Walailak Journal of Science and Technology (WJST), 9 (4) , (2012) 287-296. [3] A. Kramschuster, L.S. Turng, Fabrication of Tissue Engineering Scaffolds, Elsevier, 2013, pp. 427446.

Figure1 Schematic of electrospinning set up

Facile and Fast Fabrication of Cylindrical Graphene Field Emitters Taewoo Kim,1 Jeong Seok Lee,1 Yong Hyup Kim1 School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, 151-742, South Korea lopius04@snu.ac.kr Abstract Recently graphene has received a great deal of attention for the use of field emission source due to the outstanding field emission performances, such as a low turn-on voltage, high emission current density and long-term emission stability. We report a highly productive method to fabricate a cylindrical foam of graphene field emitter based on electrophoretic deposition of GO. Simultaneous electrophoresis and electrochemical reduction allows us to fabricate rGO foam with a low potential (4 V) and very short process time (10 sec). A vacuum drying process enables the fabrication of highly porous rGO foam which involves numerous sharp edges suitable for field emission. The fabricated graphene foam emitter shows outstanding field emission properties, such as a low turn-on electric field of 1.6 V Č?P-1, threshold field of 2.2 V Č?P-1 and long-term emission stability with a current density of 8.1 mA cm-2. The outstanding field emission characteristics are attributed to the unique two-dimensional atomic structure and superb electrical properties of graphene. Particularly, the atomically sharp edges in graphene highly focus electric field for electron emission, attributing to low threshold.[1] We envisioned that the present emitter is applicable to luminescent lighting tube and also provides a winding structure that requires high-current electron sources with high mechanical flexibility and robustness. References [1] H. Yamaguchi, K. Murakami, G. Eda, T. Fujita, P. Guan, W. Wang, C. Gong, J. Boisse, S. Miller, M. Acik, K. Cho, Y. J. Chabal, M. Chen, F. Wakaya, M. Takai, M. Chhowalla, ACS Nano 5 (2011) 4945. Figures

Prediction of toxicity for metal oxide nanoparticles 1

I. Kopernyk , V. Kovalishyn , L. Charochkina , N. Abramenko (Golovina) , W. Peijnenburg , 1 L. Metelitsya 1

- Institute of Bioorganic Chemistry & Petroleum Chemistry, Murmanskaya, 1, 02660, Kyiv, Ukraine; - Chemistry Department, Moscow State University, Leninskie Gory 1, bldg 3, 119991 Moscow, Russia; 3 - Institute of Environmental Sciences (CML), Leiden University, 2300 RA, Leiden, The Netherlands. lapaldina@gmail.com 2

Toxicity of nanomaterials is one of the most attractive scientific areas of research and taking one of the first places during recent years. There are numerous examples of already established and possible applications of using nanoparticles such as textile, cosmetics, optical, pharmacy, electronics, etc. Although the nanotechnology field is growing rapidly, the potential harmful effects of nanomaterials on human health or the environment have not yet been identified. The goal of the present study is the development of robust QSPR-based models for predicting nanoparticles toxicity (1). In this study, we used the Online Chemical Modelling Environment (OCHEM) (2) to develop a high accuracy model for predicting nanotoxicity. Data set of nanoparticles with known LC50 values were collected from different published papers and were uploaded into OCHEM (2). The main priorities were given to toxicity of metal and metal oxides nanoparticles (Fe, Ag, Pd, Ni, TiO2, ZnO, CuO, etc). About 300 data points were collected. The basic characteristics of nanoparticles such as material of nanoparticles, average particle size (APS), shape and information about experimental species were used as obligatory condition for all properties in OCHEM. Thus each record was required to incorporate information about these the most important parameters of nanoparticles. In a preprocessing step using Chemaxon Standardizer, all structures were standardized and optimized with Corina (3). Unsupervised filtering of descriptors was applied to each descriptor set before using it as a machine learning input. The overall best performance was attained by Associative Neural Network (ASNN) and k-Nearest Neighbor Method (kNN) methods. The accuracy of all individual models was estimated using cross-validation procedures. The QSPR models were developed solely based on training sets and the resulting models were validated through predicting the toxicity of the NP in the respective test sets (4). The commonly used measures of a regression model performance are the root mean square 2 error (RMSE), the mean absolute error (MAE), the squared correlation coefficient R and cross2 validated coefficient q . The OCHEM system calculates these statistical parameters for both the training and the validation sets (2). 2 Based on previously suggested recommendations, QSPR models with q > 0.5 are considered 2 to have an acceptable predictive power (4). The q coefficients for the training sets were in the range 2 0.58-0.81. q coefficients obtained for independent test prediction sets were in the range 0.66-0.73 (Table 1). The limitations and advantages of the proposed approach are discussed. Table 1. Statistical parameters M. Set Amount Descr. 1 Training set 100 47 Test set 43 2 Training set 100 132 Test set 43 a MLɌ ± machine learning technique

MLɌ ASNN kNN

0.79 ± 0.03 0.82 ± 0.05 0.59 ± 0.07 0.68 ± 0.08

0.79 ± 0.03 0.82 ± 0.06 0.58 ± 0.07 0.66 ± 0.09

RMSE

MAE

0.7 ± 0.04 0.58 ± 0.04 0.56 ±0.07 0.45 ± 0.05 1.04 ±0.07 0.85 ± 0.06 0.8 ± 0.07 0.67 ± 0.06

Acknowledgment. We would like to acknowledge the NATO Science for Peace and Security Programme (grant EAP.SFPP 984401) for funding this research. References. 1. Chatterjee R. The challenge of regulating nanomaterials. Environ.Sci.Technol, 2008, 42, 339±343. 2. http://ochem.eu/ 3. https://www.molecular-networks.com/products/corina 4. Tropsha, A. Best Practices for QSAR Model Development, Validation, and Exploitation. Mol. Inf.2010, 29, 476±488.

Multimodal plasmonics in crystalline colloidal systems Upkar Kumar1, Sviatlana Viarbitskaya1,2, Alexandre Teulle1, Jadab Sharma1, Aniket Thete1, Aurélien Cuche1, Alexandre Bouhelier2, Arnaud Arbouet1, G. Colas des Francs2, Christian Girard1, Erik Dujardin1 1 CEMES

CNRS UPR 8011 and Université Fédérale de Toulouse, 29 rue J. Marvig, 31055 Toulouse, France. Email: upkar.kumar@cemes.fr, dujardin@cemes.fr 2 Laboratoire Interdisciplinaire Carnot de Bourgogne, CNRS UMR 6303, Université de Bourgogne, 9 Avenue Alain Savary, Dijon, France.

Plasmonics has opened ways to tailor optical properties both at the macroscopic scale by allowing propagation, waveguiding and routing of plasmon polaritons but also at the nanometer-scale by taking advantage of the evanescent fields, strong confinement volumes and localized plasmonic resonances. While both regimes have been extensively studied and led to numerous applications, much less scrutiny has so far focused on the intermediate regime of micrometer-sized systems supporting a large number of confined higher order surface plasmons (SP) modes. Multimodal plasmonic systems open a new realm in which the modal behavior is better described by the SP local density of states (SP-LDOS), which is solely governed by the material properties and the boundary conditions set by the structure shape but is independent of the illumination parameters. The SP-LDOS can therefore be rationally designed to tailor the local spatial and spectral characteristics of the SP modes, while allowing information transfer over micrometer-sized distances. To reveal and exploit such spatio-modal engineering of plasmons, dissipation must be reduced by exploiting the enhanced performances of crystalline metal colloids.[1]

Figure 1: (a,b) SEM images of triangular and truncated triangular Au nanoprisms. Scale bars are 200 nm. (c, d) Confocal TPL images recorded with horizontally polarized, 700 nm exciatation. (e, f) Corresponding simulated TPL images using the GDM method. [2,3] (g, h) Total SP-LDOS maps and (i, j) corresponding AFM images of prisms with modified surface induced by plasmonic hot printing. [7]

We will first present strategies to chemically tailor the plasmonic properties of anisotropic 1D and 2D plasmonic microstructures composed of either single crystalline Au colloids [2, 3] or selfassembled superstructures [4, 5] sustaining higher order plasmonic modes. We will then demonstrate that the SP-LDOS distribution of mesoscale 2D structure can be conveniently imaged by all optical technique such as two-photon luminescence (TPL) microscopy. [2, 3, 5] The influence of wavelength, excitation polarization, particle shape and interparticle coupling on the spatial and spectral characteristic of the SP-LDOS are explored experimentally and fully confirmed by our new simulation tools based on the Green Dyadic Method (GDM). From the multimodal behavior of individual 2D colloids, we will derive a new approach of optical information processing by engineering the spatial and/or spectral distributions of higher order modes. Two routes will be presented: the near-field coupling between colloidal building blocks and the physical reshaping by focused ion beam. Our approach is applied to information propagation,[6] modal logic gates [2] and localized hot electron generation.[7] References [1] C. Girard, E. Dujardin, G. Baffou and R. Quidant. Shaping and manipulation of light fields with bottom-up plasmonic structures. New J. Phys. 10, 105016 (2008) [2] S. Viarbitskaya, A. Teulle, R. Marty, J. Sharma, C. Girard, A. Arbouet and E. Dujardin. Tailoring and imaging the plasmonic local density of states in crystalline nanoprisms. Nature Materials 12, 426 (2013)

[3] S. Viarbitskaya, A. Teulle, A. Cuche, J. Sharma, C. Girard, E. Dujardin, A. Arbouet. Morphologyinduced redistribution of surface plasmon modes in 2D crystalline gold platelets. Appl. Phys. Lett. 103, 131112 (2013) [4] S. Lin, M. Li, E. Dujardin, C. Girard and S. Mann. One-dimensional plasmon coupling by facile selfassembly of gold nanoparticle into branched networks of chains. Adv. Mater. 17, 2553 (2005) [5] T. Hoheisen, J. Cordeiro, O. Lecarme, V. Paillard, C. Girard, E. Dujardin, D. Peyrade, A Arbouet. Plasmonic Shaping in Gold Nanoparticle 3D Assemblies. J. Phys. Chem. C, 117, 23126 (2013) [6] U. Kumar, S. Viarbitskaya, A. Cuche, A. Bouhelier, G. Colas des Francs, C. Girard, E. Dujardin. in prep. [7] S. Viarbitskaya, A. Cuche, A. Teulle, J. Sharma, C. Girard, A. Arbouet, E. Dujardin. Plasmonic hot printing in gold nanoprisms. ACS Photonics, 2, 744 (2015)

Iron nanoparticles deposited on ozone pre-treated carbon nanotubes by Fluidized Bed Metal Organic Chemical Vapor Deposition 1

P. Lassègue , L. Noë , M. Monthioux , B. Caussat

LGC, ENSIACET ± INP Toulouse, UMR CNRS 5503, 4 allée Emile Monso, BP 44362, 31432 Toulouse Cedex 4, France. 2 CEMES, UPR CNRS 8011, 29 rue Jeanne Marvig, BP 94347, 31005 Toulouse Cedex 4, France. Brigitte.Caussat@ensiacet.fr Abstract Composite materials are used in the structure of planes to make them lighter, greener and more economical in fuel consumption. The aeronautic field aims now to reduce the mass of on-board electronic equipment packaging, which requires developing innovative composite materials able to evacuate thermal and electric charges while keeping appropriate mechanical features. Due to their unique physical properties, metal-coated carbon nanotubes combined with a polymer matrix represent a promising solution to face this challenge. The present work aims to uniformly deposit iron nanoparticles on the surface of Graphistrength® multi-walled carbon nanotubes (MWCNTs) tangled in balls of 400 µm in mean diameter, by Fluidized Bed Metal Organic Chemical Vapor Deposition (FB-MOCVD). A dry-mode pretreatment by ozone and a mixture of ozone/water vapor in fluidized bed is first applied, in order to increase the surface reactivity of the MWCNTs. Three atmospheres are studied during iron deposition from ferrocene (FeC10H10), involving nitrogen, hydrogen or water vapor, in order to exalt pure iron deposit. The obtained O3 or O3/H2O pre-treated MWCNTs and Fe-MWCNTs are analyzed by High Resolution Transmission Electron Microscopy (HRTEM), Thermo-Gravimetric Analysis (TGA), X-Ray Diffraction (XRD), and Scanning Electron Microscopy equipped with a Field Emission Gun and an Energy Dispersive X-ray detector (FEG-SEM-EDX). The O3/H2O pre-treatment applied between 1 h and 20 h has allowed grafting oxygen containing groups (mainly hydroxyl and carboxyl bonds) on the nanotube surface much more efficiently than using O3 alone. The amount of damaged and even opened MWCNT walls (Fig. 1) increases with the treatment duration. Whatever the atmospheres tested, the deposit from ferrocene occurs under the form of Fe 3C/Fe nanoparticles. Except in presence of hydrogen, the iron based nanoparticles are able to catalyze the formation of nanofibers or of large nanotubes. The pre-treatment increases the nucleation of iron-based nanoparticles (Fig. 2b) in comparison with non-treated MWCNTs (Fig. 2a) and then the surface reactivity of MWCNTs towards ferrocene and its gaseous products of decomposition. In comparison with the wet methods, a main advantage of dry mode pre-treatments in fluidized bed and of the fluidized bed CVD process is that they can treat large amounts of carbon nanotubes, i.e. 100 g at the lab-scale in our case and tons at the industrial scale, opening the way for a mass production of decorated MWCNTs for applications like nano-fillers of innovative multi-functional composite materials.

5 nm Figure 1: HRTEM view of a MWCNT walls after 12 h of O3/H2O pre-treatment

(a)

(b)

0.5 µm

Figure 2: TEM views of MWCNTs after iron deposition (a) without and (b) with pre-treatment

Gold electrodes functionalized with silver nanoparticles: an original and promising route for nitrate sensing in seawater. 1,2

1,3

3,4

Emilie Lebon-Tailhades , Pierre Fau , Myrtil, Kahn , Maurice Comtat , 5 5 1,3 Philippe Behra , Brigitte Dubreuil , Katia Fajerwerg . 1

Laboratoire de Chimie de Coordination (LCC), Toulouse, France (CNRS) 575$ ³6FLHQFHV HW 7HFKQRORJLHV SRXU O¶$pURQDXWLTXH HW O¶(VSDFH´ )-31030 Toulouse, France 3 Université Toulouse III - Paul Sabatier, Toulouse, France 4 Laboratoire de Génie Chimique, Toulouse, France (CNRS/INP/UPS) 5 Laboratoire de Chimie Agro Industrielle, Toulouse (INRA/INP-ENSIACET) Mail: emilie.tailhades@lcc-toulouse.fr

Abstract Nitrate is an essential plant nutrient and its concentration exerts a primary control on phytoplankton biomass and growth rates in the ocean. Historically, the concentration of nitrate has been determined by reagent-based chemical analysis in samples returned to shipboard or shore-based laboratories [1]. Moreover, traditional bench-top nitrate-analysis procedures, based on UV/Vis spectrometry, gas, ion and liquid chromatography, or capillary electrophoresis, usually requires expensive and massive instrumentation, and complex measurement procedures [2,3]. Thus these techniques are not well adapted for continuous and onsite oceanic analysis. To monitor nitrate concentration, in situ, real-time, low-power consuming, sensitive, selective and stable nitrate sensors must be developed. Electrochemistry methods are promising as they are sufficiently sensitive, relatively simple to operate, easy to miniaturize, and less power-demanding. A wide variety of systems have been developed, most of them using bare metal electrodes [3,4]. However, the use of bare unmodified electrodes for direct determination of nitrates is difficult because of the slow kinetics of the charge transfer step, dependent on several parameters (pH, interference of dissolved oxygen, etc.). We present here an original electrochemical strategy for nitrate sensing in artificial seawater at relatively neutral pH (~6). A gold disk electrode was functionalized with silver nanoparticles (AgNPs) resulting from the decomposition of a silver metal-organic precursor in solution. This synergetic approach combines the advantages of the gold electrode surface and the presence of AgNPs (Figure 1) [5,6]. The results obtained for different synthetic NO3 solutions at neutral pH using AgNPs modified-gold electrodes will be discussed and compared to the performance of gold and silver electrodes.

Fig.1. a) SEM image of the functionalized gold electrodes with AgNPs ; -4 -6 -1 b) Cyclic voltammogram of nitrate reduction 10 -10 mol.L ; c) Mechanism of the electroreduction of NO3 ions on modified electrode References [1] K. S. Johnson et al., J. of Atmospheric and oceanic technology, 30 (2013) 1854. [2] D. Kim et al., Analyst, 132 (2007) 350. [3] J.M.J. Moorcroft et al., Talanta, 54 (2001) 785. [4] J.C.M. Gamboa et al., Talanta, 80 (2009) 581. [5] K. Fajerwerg et al., Electrochemistry Communication, 12 (2010) 1439. [6] M. T. M. Kopper et al., Phys. Chem. Chem. Phys., 15 (2013) 3196.

High-performance CNT line emitters using the macroscopic mechanical clamping process Jeong Seok Lee, Jae Man Yoo, Yong Hyup Kim Seoul National University, Sillim-dong, Seoul, 151-744, Republic of Korea misty7@snu.ac.kr Abstract Many researches have clearly revealed that individual carbon nanotube (CNT) is excellent electron field emitter with a low turn-on field for emission, a high emission current density and long-term emission stability.[1] The superior emission characteristics stem from the unique one-dimensional structure and the extraordinary properties of CNT.[2] Recently, a variety of efforts have been devoted to enlarging the applicability of CNT emitters to industrial applications, including microwave amplifier tubes, high-resolution electron-beam instruments, X-ray and terahertz power sources.[3] Structural geometry of a CNT emitter is also extended to non-planar prototypes by demonstrating wrappable CNT fiber, yarn and sheet cathodes for field emission applications.[4] These recent advances in a CNT emitter have synergistically accomplished with the development of macroscopic architectures based on assembled CNTs. Various macroscopic forms of CNTs have been produced ranging through fibers, yarns, films, sheets and foams. Each structure shows unique geometry and functionality depending on the manner in which CNTs are assembled. The properties of individual CNT are unrivaled by any other materials, however it has proven difficult to simultaneously retain the intrinsic properties of CNT at engineering-relevant scales due to synthesis and fabrication issues. Moreover, several parameters need to be considered to design and fabricate a macroscopic CNT emitter, including orientation, aspect ratio, uniformity, and density of CNTs as much as the physical contacts of CNTs with a supporting electrode. We report a robust and scalable method to fabricate a high performance carbon nanotube (CNT) line emitter by using macroscopic mechanical clamping process. The process utilizes a handheld metal tong, which also serves as an electrode, applying uniaxial mechanical compression to the upper part of CNT forest in the lateral direction. While the lateral dimension of the CNT forest decreases uniaxially by 2% in the form of densely packed CNT strip, the bottom part of CNTs is subsequently detached from a substrate and is radially spreading out like bundling of flowers. As a result, a hemicylindrical shape of CNT structure strongly held with the tong electrode is achieved. Our approach is advantageous for a variety of applications, especially binder-free, density-controllable CNT electrodes, and here we demonstrate its use as a high performance CNT line emitter. With robust contact characteristics created by the mechanical clamping, a CNT line emitter shows superior field emission performance with current density of 2700 mA/cm2, net current of 40 mA and stable operation over 10 hours. Furthermore, an extremely high current of 100 mA is achieved by clamping multiple CNT forests in a tong, showing scalability of the present approach. References [1] N. de Jonge, Y. Lamy, K. Schoots, T. H. Oosterkamp, Nature. 420(2002), 393. [2] R. H. Baughman, A. A. Zakhidov, W. A. de Heer, Science. 297(2002), 787. [3] H. Sugie, M. Tanemura, V. Filip, K. Iwata, K. Takahashi, F. Okuyama, Applied Physics Letters. 78(2001), 2578. [4] L. Ci, N. Punbusayakul, J. Wei, R. Vajtai, S. Talapatra, P. M. Ajayan, Advanced Materials. 19(2007), 1719. Figures

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New structures for two-dimensional III-V binary compounds Ortwin Leenaerts, B. Schoeters, B. Partoens, and F. M. Peeters Universiteit Antwerpen, Groenenborgerlaan 171, Antwerpen, Belgium Ortwin.Leenaerts@uantwerpen.be Using first-principles calculations, we propose new two-dimensional structures for III-V binary compounds that are energetically more favorable than the theoretical structures that have been proposed so far [1,2]. These new 2D crystals show interesting mixtures of sp2-hybridized cations and sp3-hybridized anions. Their formation energies are substantially lower (up to 300 meV/atom) than the planar graphene-like and low-buckled silicene-like counterparts and are comparable to the rectangular structures proposed by Zhuang et al. [2]. The origin of the high stability of our proposed structures is twofold: (i) in contrast to the low-buckled structures, the proposed structures have no electric dipole that destabilizes the system and (ii) our structures have favorable orbital hybridizations for the cations and anions. It is well-known from molecular chemistry that group-III elements prefer planar sp2-bonded structures as in trihydrides and trihalides. Group-V elements, on the other hand, prefer tetragonal sp3bonded configurations. We found two stable configurations with these favorable hybridizations (see figure) and investigated their properties with ab initio calculations.

References [1] H. Sahin, S. Cahangirov, M. Topsakal, E. Bekaroglu, E. Akturk, R. T. Senger, and S. Ciraci, Phys. Rev. B, 80 (2009) 155453. [2] H. L. Zhuang, A. K. Singh, and R. G. Hennig, Phys. Rev. B, 87 (2013) 165415.

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Iron Oxide-PNA Nanoparticles for miRNA targeting Daniela Maggioni, Davide Dova, Andrea Guerrini, Claudio Carrara, Pramod R. Thakare, Marco Galli, Claudio Sangregorio, Silvia Cauteruccio, Monica Panigati, Emanuela Licandro, Roberta Pennati, Francesco Orsini, Paolo Arosio, Alessandro Lascialfari. Department of Chemistry, UniversitĂ degli Studi di Milano, Via Golgi 19, 20133, Milano, Italy daniela.maggioni@unimi.it Abstract The dysregulation of microRNAs (miRNAs) has been implicated in a variety of pathologies, such as inflammatory and autoimmune diseases, neurological disorders, as well as several types of cancer. Anti-miRNA platforms highly effective in in-vitro cell assays have been reported, but translation to the clinic is hampered by poor in-vivo stability of nucleic acids and ineffective uptake of nucleic acids by target cells. This study aims to overcome these obstacles by designing, producing and testing in-vivo new miRNA targeting materials constituted by Peptide Nucleic Acids (PNAs, synthetic mimics of natural DNA and RNA) [1]. Indeed, PNAs conjugate the effectiveness of the natural nucleic acids targeting with chemical/thermal stability and resistance to enzymatic biodegradation. In order to follow the fate of PNA and improve its solubility and permeability to cells, PNA has been linked to superparamagnetic iron oxide nanoparticles (SPIONs), affording new nanocomposites which will be exploited both as contrast agents for magnetic resonance imaging (MRI) and as sources of local overheating through the application of an alternating magnetic filed (Magnetic Fluid Hyperthermia, MHF). SPIONs have been prepared by a slightly modified thermal decomposition method [2] in order to optimize in particular the hyperthermia effectiveness [3]. Then, the oleate layer has been exchanged with dimercaptosuccinic acid (DMSA) which is a bifunctional small molecule, able to efficiently substitute the oleate capping agent [4]. This way both COOH and SH groups can be exploited to link PNA to the NP surface. In this work the synthesis of the magnetic NPs, their characterization and their functionalization with PNA are presented. References [1] P. E. Nielsen, M. Egholm, R. H. Berg, O. Buchardt, Science, 254 (1991) 1497. [2] P. Calcagnile, D. Fragouli, I. S. Bayer, G. C. Anyfantis, L. Martiradonna, P. D. Cozzoli, R. Cingolani, A. Athanassiou, ACS Nano, 6 (2012) 5413. [3] G. F. Goya, V. Grazu, M. R. Ibarra, Curr. Nanosci., 4 (2008) 1. [4] A. Ruiz, P. C. Morais, R. Bentes de Azevedo, Z. G. M. Lacava, A. Villanueva, M. del Puerto Morales, J Nanopart. Res., 16 (2014) 2589. Figures

Figure 1. A peptide nucleic acid repeating fragment

Figure 2. TEM image of the synthesized magnetite nanoparticles and their size distribution.

A versatile silicon platform for electrical recording of ion channels activity a,b

b,c

Raphaël Marchand , Franck Carcenac , Christophe Thibault , Laurent Malaquin , Emmanuelle b b,c Trévisiol , Christophe Vieu a Univ de Toulouse, LAAS, F-31400 Toulouse, France b LAAS-CNRS, F-31400 Toulouse, France c Univ de Toulouse, INSA, F-31400 Toulouse, France d Institut Curie, 75005 Paris, France raphael.marchand@laas.fr Abstract Ions channels are membrane proteins which allow specific ions to go through biological membrane. They play a key role in physiological mechanisms as diverse as action potential propagation, kidney function and muscle contraction. For this reason they are very valuable targets for pharmaceutical industry. Yet, high throughput drug screening on ion channels with an electrical monitoring of the channel activity ± the more informative monitoring - is limited by the lack of a system having both the flexibility and high data quality of manual patch clamp, and the high throughput of automated patch clamp [1]. Attempts have been made to develop integrated in vitro platforms to fulfil these requirements on extracted or synthetized ion channels embedded in an artificial lipid bilayer [2]. However, to our knowledge, none of these platforms allow electrical activity recordings of ion channels in a solvent-free bilayer self-formed from small unilamellar lipid vesicles containing already the ion channel of interest, which would make possible automation and high speed of these measurements. We are developing a silicon platform with an array of nanopores with a well-controlled diameter (20 nm ± 100 nm) between two electrically addressable compartments. The fabrication of silicon chip requires only a processing of the front face, and a PDMS fluidic interface allows fast integration for liquid handling, optical monitoring and electrical recordings (fig. 1) [3]. FRAP (fluorescence recovery after photobleaching) experiments have shown (fig. 3) that incubation of small unilamellar vesicles without ion channels (as a reference) on the surface of the silicon chip leads to the formation of a supported lipid bilayer, whereas electrical characterization (fig. 2) suggests that the so-formed lipid bilayer spans and seals the nanopores, leading to a lower recorded current value. These results are a first step toward ion channel monitoring with this platform. The influence of the nanopores diameter on their sealing by the bilayer together with the feasibility of ion channel electrical activity monitoring on the platform will be discussed at the conference. References [1] Yajuan, X. and al., Current Chemical Genomics, vol. 6 (2012) p. 87-92 [2] Zagnoni, M., Lab on a Chip, vol. 12 (6) (2012) p. 1026 [3] Marchand, R. and al., Microelectronic Engineering, vol. 144 (2015) p. 57-60 Figures

Polar and apolar thermoplastic polymers nanocomposites with WS2nanotubes and of Mo6S2I8-nanowires: Preparation, thermal and mechanical properties Johann G. Meier, Mariana CastrillĂłn GarcĂa, Cristina Crespo, JosĂŠ Alberto Lorda Instituto TecnolĂłgico de AragĂłn, C/ MarĂa de Luna 7-8, Zaragoza, Spain jmeier@itainnova.es Abstract Inorganic tubular and wire-like nanomaterials based on WS2 and MoSI are an interesting new alternative to carbon nanotubes [1, 2]. They show advantages such as easy synthetic access, good uniformity and solubility, and predefined electrical conductivity depending on the composition of the starting material. One of the most outstanding properties of both types of nanoparticles is their low inter-particle shear modulus, while having comparable tensile moduli to CNTs. This has the advantage that they are potentially much easier to disperse than carbon nanotubes. Also common to both types of nanoparticles (metal base W and Mo) is their excellent lubrication property This makes them highly attractive as additives for friction reduction and wear protection of polymers [3]. They are therefore very promising candidates as active fillers for polymers for mechanical reinforcement, improvement of toughness, facture toughness and fatigue behavior together with improving the tribological properties of the polymer host [4]. Hence, they hold the promise to give answers to these technological paramount property in polymers. We report on the preparation and resulting thermal and mechanical properties of polymer nanocomposites (PNC) based on nanotubes of tungsten disulfide (WS2) and nanowires of Mo6S2I8 (MoSI) with different polar and apolar thermoplastic polymers (i-PP, PET, PS, PC). The PNCs were obtained by direct incorporation of the nanoparticles into the melt of the polymer using a lab-scale conical twin-screw extruder. NPs were pretreated with ultrasound in dispersion in acetone, filtered and dried before incorporation. SEM confirmed the excellent dispersion state of the nanotubes or wires in the polymer matrices. Significant improvements of the thermal stability of the PNCs of PC and PP were observed in function of nanoparticle concentration, but surprisingly not for PET nor PS., /LNHZLVH WKH <RXQJÂśV PRGXOXV LQFUHDVHG ZLWK 13 FRQFHQWUDWLRQ RI XS WR DW ZW We will discuss the thermal and mechanical effects. References 1. R. Tenne and G. Seifert, Ann. Rev. Mater. Res., 39 (2009) 387. 2. D. Mihailovic, Prog. Mater Sci., 54 (2009) 309. 3. J. G. Meier, A. Mrzel et al., physica status solidi (a), 210 (2013) 2307. 4. M. Naffakh, A. M. DĂez-Pascual et al., Prog. Polym. Sci., 38 (2013) 1163. PC PC + 1.5 wt% MoSI PC + 1.5 wt% WS2

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Electronic bandgap and exciton binding energy of layered semiconductor TiS 3 1

Aday J. Molina-Mendoza , Mariam Barawi , Robert Biele , Eduardo Flores , José R. Ares , Carlos 2 1 1,4 3 2 Sánchez , Gabino Rubio-Bollinger , Nicolás Agraït , 5REHUWR '¶$JRVWD , Isabel Ferrer , and Andres 4 Castellanos-Gomez . 1

Dpto. de Física de la Materia Condensada, Universidad Autónoma de Madrid, Campus de Cantoblanco, E-28049 Madrid, Spain 2 Materials of Interest in Renewable Energies Group (MIRE Group), Dpto. de Física de Materiales, Universidad Autónoma de Madrid, Campus de Cantoblanco, E-28049 Madrid, Spain 3 ETSF Scientific Development Center, Dpto. de Física de Materiales, Universidad del País Vasco, E20018 San Sebastián, Spain 4 Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-nanociencia), Campus de Cantoblanco, E-18049 Madrid, Spain aday.molina@uam.es We present a study of the electronic and optical bandgap in layered TiS3, an almost unexplored semiconductor that has attracted recent attention because of its large carrier mobility and inplane anisotropic properties, to determine its exciton binding energy. 1-4 We combine scanning tunneling spectroscopy and photoelectrochemical measurements with random phase approximation and BetheSalpeter equation calculations to obtain the electronic and optical bandgaps and thus the exciton binding energy. We find experimental values for the electronic bandgap, optical bandgap and exciton binding energy of 1.2 eV, 1.07 eV and 130 meV (Fig. 1), respectively, and 1.15 eV, 1.05 eV and 100 meV for the corresponding theoretical results. The exciton binding energy is orders of magnitude larger than that of common semiconductors and comparable to bulk transition metal dichalcogenides, making TiS3 ribbons a highly interesting material for optoelectronic applications and for studying excitonic phenomena even at room temperature. [1] J. O. Island, M. Buscema, M. Barawi, J. M. Clamagirand, J. R. Ares, C. Sanchez, I. J. Ferrer, G. A. Steele, H. S. J. van der Zant and A. Castellanos-Gomez, Advanced Optical Materials 2 (7), 641-645 (2014). [2] J. O. Island, M. Barawi, R. Biele, A. Almazán, J. M. Clamagirand, J. R. Ares, C. Sánchez, H. S. J. van der Zant, J. V. Álvarez, R. D'Agosta, I. J. Ferrer and A. Castellanos-Gomez, Advanced Materials DOI: 10.1002/adma.201405632, (2015). [3] I. J. Ferrer, J. R. Ares, J. M. Clamagirand, M. Barawi and C. Sánchez, Thin Solid Films 535 (0), 398-401 (2013). [4] M. Barawi Moran, E. Flores Cuevas, I. Jimenez Ferrer, J.-R. Ares and C. S, Journal of Materials Chemistry A DOI: 10.1039/C5TA00192G (2015).

Figure 1. a) Colormap histogram of STS current-voltage curves (current in absolute value). A representative current-voltage curve is plotted in solid black line. Inset: AFM topographic image of TiS3 ribbons. b) Photocurrent density as a function of light wavelength (energy). The optical bandgap energy is determined by the point where the linear fit cuts the zero photocurrent density (highlighted in the inset).

Electrochemical Characteristics of Nano-size Li4Ti5O12/C as Anode Materials of Lithium-ion Battery

Byung-Ki Na*, Sang-Baek Kim Deaprtment of Chemical Engineering, Chungbuk National University, Chungdaero 1, Seowongu, Cheongju, 362-763, Korea nabk@chungbuk.ac.kr Abstract Lithium ion battery has been extensively used to mobile electronics, electric vehicle, and energy storage system. In order to increase the energy density many research have been studied for the development of cathode, anode, and electrolyte. Li4Ti5O12 can be used as the anode material. Lithium titanium oxide has a spinel-type structure and has unique insertion-deinsertion mechanism. It is “zerostrain” insertion material and long cycle life and excellent cycle characteristics. Theoretical capacity of + Li4Ti5O12 is 175 mAh/g. Formal potential of Li insertion is approximately 1.55 V (Li vs. Li). Carbon is regarded as an ideal conductive additive since carbon-based materials (CNTs, graphene) have superior electrical conductivity. Li2Co3, TiO2, CNT, and graphene were mixed with planetary ball mill. The mixture was dried at 80䉝 for 6h and calcined at 800䉝 for 6h. It was heat-treated at 700䉝 for 12h under propylene flow condition. Carbon-coated Li4Ti5O12 synthesized via a simple solid-state reaction(CNTs and graphene) and a vapor- state reaction(propylene gas). Different types of carbons were added to the precursor mixture to synthesize Li4Ti5O12 and showed improved discharge/charge and cycling properties. Grapheneembedded LTO has best performance 178.5 mAh/g at 0.1C and capacity recovery percentage was larger than 98%. References [1] K.M. Colbow, J.R. Dahn, and R.R. Haering, J. Power Sources, 26 (1989) 397. [2] K. Zaghib, M. Armand, and M. Gauthier, J. Electrochem. Soc., 145 (1998) 3135. [3] S.W.Woo and K.D.K. Kanamura, Electrochim. Acta, 53 (2007) 79. Figures LTO

180

LTO LTO/P LTO/C LTO/G

150 LTO/graphene

LTO/CNTs

LTO/propylene

Capacity [mAh/g]

intencity (a.u)

rutile TiO2

120

0.1C

0.1C 0.2C

0.5C 1C

30 0

LTO 10

2 Theta degree

Fig. 1. XRD patterns of Li4Ti5O12, Li4Ti5O12/Propylene, Li4Ti5O12/CNTs , Li4Ti5O12/graphene

10 15 Cycle number

Fig. 2. Cycle performance of Carbon-coated Li4Ti5O12

RT Synthesis of Air-Stable and Size-Tuneable Luminescent ZnS coated Cd3P2 Nanocrystals with High Quantum Yields C. Nayral, W-S. Ojo, S. Xu, B. Chaudret, F. Delpech Université de Toulouse ; INSA, UPS, CNRS ; LPCNO (Laboratoire de Physique et Chimie des NanoObjets), Toulouse, France. cnayral@insa-toulouse.fr Abstract The high temperatures usually required for the synthesis of quantum dots (QDs) are a major drawback, which, beyond obvious energetic concerns, represents a significant limit in the implementation of simple “routine” synthesis methods to ensure run-to-run reproducibility, automation possibilities, and standardization of the nanomaterials. Synthetic protocol to cadmium phosphide QDs, which is a conspicuous material by virtue of its ability to absorb and emit in the near infrared wavelength window (narrow bandgap -0.55 eV- and large excitonic radius -18 nm) also suffer from this major limitation (T> [1,2] We will show how the design of a suitable precursor allows breaking this technological 250°C). limitation and allows the room temperature synthesis of air-stable, size-tunable, and high optical quality [3] (quantum yields > 50%) Cd3P2/ZnS QDs. A large range of emissivity is easily covered (from ~600 nm to 1400 nm) thanks to the modulation of the concentration of reactants and of the temperature (30°C, 90°C). The strategy followed to achieve this two steps synthesis at low temperature is based on the choice and design of highly reactive and soluble precursors, Cd(OAc)2(OAm)2 (OAc = acetate, OAm = octylamine) and (TMS)3P (tris(trimethylsilyl)phosphine) for the formation of the Cd3P2 cores and 1 13 31 Zn(OAc)2(OAm)2 and C2H4S (ethylene sulphide) for the coating process. H, C and P solution and solid-state NMR studies will be presented and show the presence of a thin layer of oxide at the interface Cd3P2/ZnS and of tightly bond ligands (acetate and octylamine) at the surface of the QDs. References [1] R. Xie, J. Zhang, F. Zhao, W. Yang, X. Peng, Chem.Mater. 22(13) (2010) 3820. [2] S. Mia, S. G. Hickey, B. Rellinghaus, C. Waurisch, A. Eychmüller, J. Am. Chem. Soc. 132 (16) (2010) 5613. [3] W.-S. Ojo, S. Xu, F. Delpech, C. Nayral, B. Chaudret Angew. Chem. Int. Ed. 51 (2012) 738.

Figures

ZnS Cd3P2

Fig.1 Concentration effect on the PL emissivity of core/shell Cd3P2/ZnS QDs

Application of colloidal metalloporphyrin nanoparticles in catalytic oxidation reactions Fatemeh nejabat, Saeed Rayati Department of Chemistry, K.N. Toosi University of Technology, P.O. Box 16315-1618, Tehran 15418, Iran rayati@kntu.ac.ir (S. Rayati). Abstract Catalytic oxidation of organic substrates with different oxygen donors is one of the most effective methods in producing the important materials mainly for organic synthetic chemistry. Metalloporphyrins have been applied as biomimetic models of cytochrome P450s in the catalytic oxidation reactions [1].since reusability of the catalyst become an important factor in industrial level, an efficient way in the development and improvement of catalytic systems is using heterogeneous catalysts. In the last decade, many scientists pay attention to the nanocatalyst because of the importance of particle size and surface area in the catalytic activity [2]. Employing different kinds of porous as support is a common method for preparation of nanocatalysts [3]. Unfortunately, most of the supports are expensive and also decrease catalytic activity. A new technique for development of nanocatalysts is preparing stable colloidal nanoparticles [4]. In present research, we prepare stable colloidal nanoparticles of Č&#x2022;-brominated metalloporphyrins in the presence of stabilizing agent (PEG) under ultra-sound irradiation and used them as catalyst in the oxidation of olefins. The effect of various parameters on the stability and particle size of colloidal nanoparticles were also investigated. References

[1] R.A. Sheldon, Metalloporphyrins in Catalytic Oxidations, Marcel Dekker, New York, 1994.

[2] A. Corma and H. Garcia, Adv. Synth. Catal., 384 (2006) 1391.

[3] S. Rayati, S. Zakavi, P. Jafarzadeh, O. Sadeghi, M.M. Amini, J. Porph. Phthal. 16 (2012) 260.

[4] A. Aggarwal, S. Singh, C.M. Drain, J. Porph. Phthal. 15 (2011) 1258Âą1264.

Figures

Novel conductive ZnO:Zn composites for thin film solar cell back reflectors application 1,2

1,2

Li Qin Zhou , Raul SimĂľes , BĂĄrbara Gabriel , Qi Hua Fan ,Victor Neto

1,2

Centre for Mechanical Technology and Automation, Department of Mechanical Engineering University of Aveiro, 3810-193 Aveiro, Portugal 2 Aveiro Nanotechnology Institute, University of Aveiro, 3810-193 Aveiro, Portugal 3 Department of Electrical Engineering and Computer Science, South Dakota State University, USA vneto@ua.pt Abstract Dielectric thin films of high- and low-refractive index are the essential building blocks for optical coatings considering solar cells applications [1]. In order to achieve high sputtering rates and superior film quality, novel conductive ZnO:Zn composites have been developed, which become conductive once the metal Zn reach a critical ratio, as presented in Fig. 1. Optimized ZnO:Zn produced target have been characterized and used to sputter optical conducting films that were then studied for structural, optical and electrical properties characterization. Experiments on solar cell using ZnO:Zn sputtered thin films were also conducted. When conductive particles are dispersed into a nonconductive matrix and the amount of the conductive phase increases from zero up to a critical volume fraction of percolation [2], one particle contact with neighbors and form finite conductive path where the host material is non-conductive. Near the critical volume, a conductive network is formed and the resistivity of the entire composite abruptly decreases. The critical fraction of the conductive Zn phase is ~20% in weight in the present study. SEM/EDX analysis was performed to confirm this assumption. Transmittance spectra of ZnO films prepared by RF sputtering from ZnO:Zn displayed similar transparency as other typical used optical coatings. References [1] H.A. Macleod, Thin-Film Optical Filters, Third Edition, IOP Publishing, Bristol and Philadelphia (2001) [2] D. S. McLachlan, M. Blaszkiewicz and R. E. Newnham, J. Am. Ceram. Soc. 73, 2187 (1990).

Figures

Fig.1 Resistivity versus x value for (1-x)ZnO+xZn compositions.

Chemiresistors Based on Gold Nanoparticle Supercrystals: Sensing Mechanism Studied by in Situ GISAXS Natalia Olichwer, Andreas Meyer, and Tobias Vossmeyer Institute of Physical Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany Natalia.Olichwer@chemie.uni-hamburg.de Assemblies of ligand stabilized gold nanoparticles have demonstrated remarkable potential for vapor sensing applications. The main features of gold nanoparticle based chemiresistors are their high sensitivity, adjustable selectivity, fast and reversible responses, low power consumption and the tunability of their underlying electrical properties.[1,2] It is generally accepted that the sensing mechanism involves (at least) both swelling and sorption induced changes in permittivity. While swelling leads to higher resistivities, due to increased tunnel distances between neighboring particles, an increase in permittivity counteracts, and sometimes even over-compensates, this effect.[3]However, repeatedly, findings have been reported which are difficult to explain by this model.[4] Thus, to enable the rational development and target specific optimization of such sensors, a deeper and more quantitative mechanistic understanding is indispensable. On the experimental side, this requires measurements enabling the correlation of the chemiresistive response with the actual change in interparticle distance and the absolute amount of sorbed analyte. As shown previously, swelling of ordered nanoparticle assemblies can be probed in situ via grazing incidence small angle x-ray scattering (GISAXS).[5,6] Here, we use GISAXS to study simultaneously swelling and resistive responses of supercrystals assembled from dodecanethiol stabilized gold nanoparticles. Additionally, the mass uptake due to analyte sorption was quantified using quartz crystal microbalances. When exposed to toluene, 4-methyl-2-pentanone or 1-propanol vapors, with concentrations ranging from 1000 to 10000 ppm, the supercrystals responded with a fast reversible increase in resistance and interparticle distance. All three measurements revealed the same trend concerning the selectivity, which was controlled by the solubility match between the dodecanethiol ligand and the solvent. The measurements allow us to test and further develop the above mentioned model. Further, it was observed that contaminants originating from the particle synthesis can have a considerable effect on the lattice constants, the swelling and the chemiresistive responses. [1] [2] [3] [4] [5] [6]

F. J. IbaĂąez, F. P. Zamborini, Small, 2 (2011) 174. N. Olichwer, E. W. Leib, A. H. Halfar, A. Petrov, T. Vossmeyer, ACS Appl. Mater. Interfaces, 11 (2012) 6151. Y. Joseph, A. Peic, X. Chen, J. Michl, T. Vossmeyer, A. Yasuda, J. Phys. Chem. C, 34 (2007) 12855. A. W. Snow, M. G. Ancona, D. Park, Langmuir, 44 (2012) 15438. Y. Wan, N. Goubet, P.-A. Albouy, N. Schaeffer, M.-P. Pileni, Langmuir, 44 (2013) 13576. M. C. Dalfovo, L. J. Giovanetti, J. M. Ramallo-LĂłpez, R. C. Salvarezza, F. G. Requejo, F. J. IbaĂąez, J. Phys. Chem. C, 9 (2015) 5098.

Laser Induced Nanostructures on ZnO Thin Films for Morphology-controlled Gas Detection U. Palomares, M. Martinez-Calderón, I. Castro-Hurtado, M. Gomez-Aranzadi, A. Rodríguez, S.M. Olaizola, E. Castaño, G. Gª Mandayo CEIT and Tecnun (University of Navarra), Paseo Manuel Lardizabal 15 20018, Donostia, Spain upalomares@ceit.es Abstract In the last years the social conscience towards climate change and greenhouse effect, as well as the restrictive laws against gas emissions, have increased. These facts lead into a need for the air quality monitoring on a real-time basis. Nowadays, several specialized measurement systems can be found in the market. However, these are usually too bulky, expensive and not valid for all environments [1]. In this context, new micro/nanotechnologies are required in order to create improved devices. They should be capable of overtaking the actual barriers while they work with a minimum energy consumption. Taking into account the actual scenario, chemical sensors based on metal oxide semiconductors represent a promising solution. Indeed, ZnO, SnO2, In2O3 or TiO2 are well known for their cost-effectiveness, fast response and high sensitivity when exposed to target gases [2,3]. On a general basis, chemical gas sensors are based on the electric response variation caused by the target gas-sensitive material surface chemical reaction. Particularly, conductometric gas sensors suffer a change in their resistance, which is proportional to the detected gas amount [4]. On the other hand, the detection capacity is determined by the reaction temperature as well as the morphology of the semiconductor. Given the fact that this last parameter is highly dependent on the fabrication process, nanostructuring of the sensing material surface is an approach that can be applied to maximize the surface area and increase the sensorial properties of the device. In the present study zinc oxide is selected as sensing material. Thin films are deposited onto alumina substrates by RF reactive magnetron sputtering with a metal oxide target of 99.999% purity. The -3 sputtering is performed under Argon gas with a pressure of 5·10 mbar and the RF power is maintained at 100 W. The thickness measured with a KLA Tencor Profilometer for a deposition time of 1h is 150nm [5]. On a second step, zinc oxide thin films are processed by laser interference lithography (LIL) with the aim of obtaining a morphology change of the sensing material. The employed system uses a tripled Qswitched Nd:YAG laser source with an output wavelength of 355 nm [6]. The pulse duration is 8 ns and the maximum frequency can be 10 Hz. In addition, the initial laser beam is divided into two by a beamsplitter and then recombined in order to create an interference pattern on the zinc oxide-alumina wafer surface. This interference pattern consists of a series of lines corresponding to the intensity maxima and minima. The influence of several parameters on the surface patterning by LIL and therefore on the resulting sensing layer surface area has been studied. First of all, the fluences and number of pulses used for the 2 patterning were varied in a range from 85 to 145 mJ/cm and up to 4 pulses, respectively. This allows to determine the energy threshold of the material, which is also affected by the number of accumulation laser pulses [7]. Furthermore, two different periods (300 and 500 nm) were selected and compared to the obtained ones on the nanostructured surface, so that the influence of material´s thermal diffusivity could be derived. All experiments were carried out at atmospheric pressure in a class 100 clean-room [8]. Figure 1 shows the morphological progression of ZnO thin films caused by single pulsed laser 2 interference lithography with fluences between 0 and 145 mJ/cm and a period of 300 nm. The resultant irradiation lines are translated into a localized porosity change, which can be tuned by the parameters mentioned above, in order to find the optimized surface area. As shown in the micrograph, a periodic structure composed of lines with different grain sizes is obtained. The lines which correspond to minimum intensity, i.e. non-processed area, are formed by grains in the range of 30 nm. On the other hand, the region of maximum intensity is melted and shows a planar surface. Moreover, for a fixed period, melted lines´ width increases with the fluence of the incident radiation.

Future work aims to implement this surface modification technique directly on the sensing zone of a fully synthetized conductometric gas sensor. On a final step, sensor´s electrical response in the presence of target gases will be tested under real conditions. This way, it will be possible to study in detail the influence of sensing properties as a function of the porosity and specific surface area of the ZnO layer. References [1] N. Barsan, D. Koziej, U. Weimar, Sensors and Actuators B, vol. 121, pp. 18-35, 2007. [2] C.A Papadopoulos, D.S Vlachos, J.N Avaritsiotis, Sensors and actuators B, vol. 32, pp. 61±69, 1996. [3] K. Wetchakun, T. Samerjai, N. Tamaekong, et al., Sensors and actuators B, vol. 161, pp. 580±591, 2011. [4] X. Chu, T. Chen, W. Zhang, et al., Sensors and Actuators B, vol. 142, pp. 49-54, 2009. [5] I. Castro-Hurtado, J. Herrán, N. Pérez, et al., Sensor letters, vol. 9, pp. 1±5, 2011. [6] T. Tavera, N. Pérez, A. Rodríguez et al., Applied Surface Science, vol. 258, pp. 1175-1180, 2011. [7] A. Datcu, A. Pérez del Pino, C. Logofatu, et al., Nanoscience Advances in CBRN Agents Detection, Information and Energy Security, Springer, Netherlands, 2015. [8] I. Castro-Hurtado, T. Tavera, P. Yurrita, Applied Surface Science, vol. 276, pp. 229-235, 2013. Figures

CARBON NANOTUBE NET AS A CONDUCTIVE AND TRANSPARENT FILM FOR SOLAR ENERGY CONVERSION Sergio Pinilla, José Lorenzo Balenzategui, C. Morant, E. Elizalde Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain sergio.pinilla@uam.es Abstract Vertically aligned silicon nanowires arrays have been grown through a metal assisted chemical etching method [1] obtaining a heavily absorbing surface. Over this surface, a transparent and conductive net of carbon nanotubes (CNTs) has been formed by chemical vapor deposition method [2]. The optical and electrical properties of this net have been studied. The influence of the catalyst deposition method in the mentioned properties and structure has also been evaluated. The optical characterization of the net has been performed by the study of its hemispherical reflectance and the electrical properties have been obtained by 4-point probe method and I-V curves of the surface. A high transmittance of the net (over 99%) in the 300-900 nm range is reported. Also, a good sheet resistance value has been obtained (around N Ƒ) for such a thin carbon nanotube net. In addition, Raman spectroscopy show that the carbon nanotube net is formed by single walled CNTs, according to the literature [3]. The structural data of the CNTs obtained by Raman has been correlated with the observed optical and electronic properties. References [1] Z.P. Huang, N. Geyer, P. Werner, J. de Boor, U. Gosele, Advanced Materials. 23 (2011) 285308. [2] C. Morant, T. Campo, F. Marquez, C. Domingo, J.M. Sanz, E. Elizalde, Thin Solid Films. 520 (2012) 5232-5238. [3] M.S. Dresselhaus, G. Dresselhaus, R. Saito, A. Jorio, Physics Reports-Review Section of Physics Letters. 409 (2005) 47-99. Figures

Figure 1Reflectance measurements on samples with and without CNTs

Figure 2 CNT net over the SiNWs

Study of the Possibility of Nanodiamond Particles Transformation into Carbon Onions in Metal Matrix Composites when Heated in Non-Oxidizing Conditions 1

V.A.Popov , E.V.Vershinina 1 2

National University of Science and Technology Âł0,6,6Â´ /HQLQVN\ SURVSHFW , Moscow, Russia Lomonosov Moscow State University of Fine Chemical Technology, prospect Vernadskogo, 86, Moscow, Russia popov58@inbox.rul

Abstract It is known that when heated in non-R[LGL]LQJ FRQGLWLRQV DW PRUH WKDQ Â&#x192;É&#x2039;, nanodiamonds are transformed into onion-like carbon nanoparticles [1]. Various methods have been developed to produce metal matrix composites with both agglomerated and non-agglomerated nanodiamond reinforcing particles [2]. What is of interest here is the possibility of transformation of nanodiamonds contained in a metal matrix in carbon onions, since it enables to produce a new composite material. Copper and nickel were taken as the matrix. Composite granules were produced by mechanical alloying. Annealing was performed in argon or in vacuum: copper specimens were heated up to 1050Â&#x192;É&#x2039;, nickel specimens Âą up to 1200Â&#x192;É&#x2039;. The produced material was studied by scanning and transmission electron microscopy and differential scanning calorimetry (DSC) methods. Fig.1 shows an onion-like particle in a copper matrix, suggesting the possibility of nanodiamonds transformation into carbon onions, if nanodiamonds are contained in a metal matrix. But there was another effect discovered. The composite granules after they were taken from the planetary mill jars where mechanical alloying had taken place were subject to increased oxidation at room temperature. The oxides produced chemically reacted with nanodiamonds (chemical element Âą carbon) when heated. The DSC curves clearly show the beginning of these chemical reactions (Fig.2). It results in the decrease of nanoparticle content in a composite. To eliminate this adverse effect, all operations shall be carried out in non-oxidizing conditions. References [1] V. A. Popov, A. V. Egorov, S. V. Savilov, V. V. Lunin, A. N. Kirichenko, V. N. Denisov, V. D. Blank, O. M. Vyaselev, T. B. Sagalova. Journal of Surface Investigation. X-ray, Synchrotron and Neutron Techniques, 2013, No.6, pp 1034-1043 [2] V.A.Popov. Metal matrix composites with non-agglomerated nanodiamond reinforcing particles. In: Xiaoying Wang (Ed.) Âł1DQRFRPSRVLWHV 6\QWKHVLV &KDUDFWHUL]DWLRQ DQG $SSOLFDWLRQVÂŞ 1RYD 6FLHQFH Publishers, New York, 2013, pp.369-401.

Figure 1. Onion-like carbon nanoparticle inside copper matrix (TEM)

b Figure 2. DSC curves for composites: a-Ni+ND; bCu+ND. Reaction between ND and oxides starts around 550Â&#x192;C

Strain engineering of Schottky barriers in single and few-layer MoS2 vertical devices 1

Jorge Quereda , Andrés Castellanos-Gomez , Nicolás Agräit

1,2,3,4

and Gabino Rubio-Bollinger

1,3,4

Departamento de Fisica de la Materia Condensada. Universidad Autónoma de Madrid, Madrid, E2 28049, Spain. Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA ± Nanociencia), E3 28049, Madrid, Spain. Instituto de Ciencia de Materiales Nicolás Cabrera, E-28049, Madrid, Spain. 4 Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049, Madrid, Spain. jorge.quereda@uam.es Abstract ± Two-dimensional transition metal dichalcogenides have demonstrated a huge potential for the development of novel electronic and devices. Among them, atomically thin MoS2 raises special interest due to its relatively high carrier mobility and intrinsic 1.8 eV bandgap [1, 2]. Further, it has been recently demonstrated that the band structure of atomically thin MoS2 crystals can be modified applying uniaxial or biaxial strain [3], enhancing even more their technological possibilities. In this work we study experimentally the electron transport through vertical metal-atomically thin MoS2metal junctions, using a conductive AFM tip to contact single and few-layer MoS2 crystals deposited onto a metallic substrate. Remarkably, even when the MoS2 crystal is just one layer thick, two metalsemiconductor barriers are formed at the tip-MoS2 and MoS2-substrate interfaces. As a consequence, the structure shows a strong rectifying I-V characteristic. Furthermore, the rectification ratio of the I-V characteristic can be modified by applying mechanical pressure to the MoS2 crystal with the AFM tip. To further demonstrate the studied devices, we use them to rectify a periodic voltage, controlling the rectification ratio through the mechanical pressure applied with the AFM tip.

Figure 1. (a) Schematic of the experimental setup: The semiconducting MoS2 flake is sandwiched between the conductive ITO substrate and the AFM tip. Two metal-semiconductor junctions in series are thus obtained: one at the interface between the conductive tip and the MoS 2 flake and other at the interface between the MoS2 flake and the ITO substrate. A Schottky barrier is formed at each of these interfaces. The I-V characteristic of the structure is obtained by applying a voltage bias (V) between the conductive tip and the ITO substrate. (b) Measured I-V characteristics of an atomically thin MoS2 flake under four different tip-flake contact forces: 20, 40, 60 and 80 nN. Black lines are least square fittings to a double-barrier model. Inset: Force-dependent rectification ratio measured at ± 1V. 1. 2. 3.

Radisavljevic, B., et al., Single-layer MoS2 transistors. Nature nanotechnology, 2011. 6(3): p. 147-150. Krasnozhon, D., et al., MoS2 transistors operating at gigahertz frequencies. Nano letters, 2014. 14(10): p. 5905-5911. Castellanos-Gomez, A., et al., Local strain engineering in atomically thin MoS2. Nano letters, 2013. 13(11): p. 5361-5366.

Synthesis and Characterization of Novel Nano-Cocoon like Structures of Polymer-CNT Nanocomposite 1

Hindumathi R , Haridoss Prathap , Sharma C.P. 1

Indian Institute of Technology Madras, Chennai, India. Sree Chitra Tirunal Institute for Medical Sciences & Technology(SCTIMST), Thiruvananthapuram, India. hinuthi@gmail.com

Abstract Multi-Walled Carbon NanoTubes (MWCNTs) dispersed in Polyethylene Glycol (PEG) were broken into small tubes by vortexing with tungsten-carbide balls for about 15 hrs and centrifuged using differential centrifugation for separating the CNTs size-wise. Centrifugation is being used for sorting of MWCNTs based on their length[1]. PEG 400 of various concentrations was used as centrifugation medium. The separated fractions of CNT-PEG solution were further pelletised and purified using high speed centrifugation. The pellets were dispersed again in water to get nano-cocoon like structures in one of the fractions, when observed under field emission scanning electron microscopy. High resolution transmission electron microscopy of the cocoons reveals polymer capsules of 100-200 nm in dimension with few CNTs. These structures can be used as biocompatible drug delivery particles for longer blood circulation time.

References [1] Qing-Ping Feng, Xu-Ming Xie, Yi-Tao Liu, Yan-Fang Gao, Xiao-Hao Wang and Xiong-Ying Ye, Letters to the Editor / Carbon, 45 (2007) 2307Âą2320.

Figures A

Fig.1 (A) FE-SEM image and (B) HR-TEM image of PEG-CNT nano-cocoons

Investigating nanoplasmonics in diamondoid-metal cluster hybrids 1

Torbjörn Rander , Tobias Zimmermann , Andre Knecht , Robert Richter , Theresa Höhne , 2 2 2 1 Merle I. S. Röhr , Jens Petersen , Roland Mitric and Thomas Möller 1 2

Berlin Institute of Technology, Hardenbergstr. 36, 10623 Berlin, Germany University of Würzburg, Emil-Fischer-Str. 42, 97074 Würzburg, Germany torbjorn.rander@mailbox.tu-berlin.de

Abstract 3

Diamondoids, a class of sp hybridized carbon nanostructures, show size and shape dependent optical properties [1]. They are interesting as light-emitting materials due to their intrinsic UV fluorescence. However, the fluorescence quantum yield of pristine diamondoids is relatively low. Plasmon resonance effects are known to enhance absorption and emission in noble metal particles in the nanometer size regime strongly [2, 3]. Combinations of diamondoids and sub-nanometer metal clusters are promising candidates to study the fundamentals of such interactions in a size regime where experimental parameters can be controlled by the addition or removal of single atoms. While such effects are widely studied in larger nanoparticles, only few studies have been performed in this size regime before, see for example [4]. We present an experimental set-up for the investigation of nanoplasmonics in size-selected diamondoid-metal cluster hybrids (see figure 1) together with first experimental results on the UV absorption of such systems, acquired using synchrotron radiation. These proof-of-principle experiments, together with recent theoretical work [5], pave the way for further experimental investigations of these and similar systems, in particular of their fluorescence yields, where enhancement or quenching thereof presents an especially interesting direction of inquiry. References [1] G. A. Mansoori, P. L. B. de Arujo and E. S. de Arujo, „Diamondoid Molecules: With Applications in Biomedicine, Materials Science, Nanotechnology and Petroleum Science“, World Scientific Press, (2012) [2] P. Anger, P. Bharadwaj und L. Novotny, „Enhancement and Quenching of Single-Molecule Fluorescence,“ Physical Review Letters, 96, 113002 (2006) [3] F. Tam, G. P. Goodrich, B. R. Johnson und N. J. Halas, „Plasmonic Enhancement of Molecular Fluorescence,“ Nano Letters, 7, 496 (2007) [4] A. Kulesza, R. Mitric und V. Bonacic-Koutecky, „Silver cluster induced absorption enhancement and confirmational control of peptides,“ The European Physics Journal D, 52, 203 (2009) [5] P. G. Lisinetskaya und R. Mitric, „Ab initio simulations of light propagation in silver cluster nanostructures,“ Physical Review B 89, 035433, (2014)

Figures

Figure 1: Experimental set-up (center) with fluorescence extension (inset left) and calculated orbitals of a HOMO-LUMO excitation in a triamantanethiol-Ag hybrid.

Nobel Photocatalytic Method to observe grain boundaries of large-area graphene on Copper by optical microscopy Sempere B., BermĂşdez P., Colominas C. Materials Engineering Group-GEMAT, IQS School of Engineering Âą Universitat Ramon Llull, Via Augusta 390, Barcelona, Spain bernatsemperen@iqs.edu Abstract It is well known that CVD graphene films grown on copper are polycrystalline in nature and that its properties depend on grain boundaries and defects. Several methods and techniques have been applied to study the presence of graphene grain boundaries and resulting domain sizes. Atom resolution complex techniques like STM and TEM allow visualization of individual atom placement inside graphene lattice but are in practice limited to areas under 1 micrometer. There is still a lack of a convenient detection technique for simple large-area graphene grain boundary observation that allow straightforward graphene crystal size quality control. In 2012 two methods were reported to reveal domains and grain boundaries of graphene on copper by optical microscopy: (i) Thermal oxidation [1] in air at 160ÂşC followed by H2O2 treatment; (ii) Photo-oxidation [2] by UV light through grain boundaries in a humidity controlled chamber. Thermal oxidation it is particularly useful to reveal graphene coated areas, but it has a poor resolution for grain boundary analysis. Photo-oxidation successfully reveals grain boundaries and defects, however causing excessive damage to copper substrate. Our group have developed a photocatalytic oxidation method using TiO2 suspensions in water at room temperature to produce a highly controllable mild oxidation of copper through graphene defects. Fig 1 shows optical microscope images of original CVD graphene on copper and graphene grain boundaries revealed by different oxidation techniques. It can be observed that photocatalytic technique yields a controlled oxidation of copper, better suited for grain size statistical analysis. References [1] [2]

C. Jia, J. Jiang, L. Gan, and X. Guo, Sci. Rep., Âł'LUHFW RSWLFDO FKDUDFWHUL]DWLRQ RI JUDSKHQH JURZWK DQG GRPDLQV RQ JURZWK VXEVWUDWHV Â´ 2(2012) 707. D. L. Duong, G. H. Han, S. M. Lee, F. Gunes, E. S. Kim, S. T. Kim, H. Kim, Q. H. Ta, K. P. So, S. J. Yoon, S. J. Chae, Y. W. Jo, M. H. Park, S. H. Chae, S. C. Lim, J. Y. Choi, and Y. H. Lee, 1DWXUH Âł3URELQJ JUDSKHQH JUDLQ ERXQdaries with optical microscopy.Â´ 490(2012) 235Âą239.

Figures

Fig 1. From left to right: (i) Original graphene on copper, (ii) thermal oxidation of copper through graphene, (iii) catalytic photo-oxidation of copper through graphene.

Light-Induced Switching of Tunable Single-Molecule Junctions 1

Torsten Sendler , Katharina Luka-Guth , Matthias Wieser , Lokamani , Jannic Wolf , Manfred 1 1 1 2 2 1 Helm , Sibylle Gemming , Jochen Kerbusch , Elke Scheer , Thomas Huhn , and Artur Erbe 1

Helmholtz-Zentrum Dresden – Rossendorf, Dresden, Germany 2 Universität Konstanz, Konstanz, Germany a.erbe@hzdr.de

Abstract Molecular electronics aims at scaling down electronics to a regime of 1-2 nm for single components. In order to design electrical circuits which base on the properties of single molecules, reliable contacts to single organic molecules have to be built and the properties of those junctions need to be characterized. We have demonstrated that the mechanically controllable break junction (MCBJ) technique can be successfully used to determine the properties of electronic transport through single organic molecules and that the participating molecular energy levels and the metal-molecule coupling can be characterized 1 using this technique . Further developments are based on the use of more complex molecules, which 2,3 can, for example, be used as single molecule switches . We present the first demonstration of a single molecule junction, in which the molecule is switched in situ from the non-conducting “off”-state to the conducting “on”-state. The molecule is attached to gold electrodes via thiol linkers and can be switched by irradiation with UV-light (see figure). The conductance of the single molecule junctions is determined by recording the resistance during stretching the junction. Additionally, current voltage characteristics are recorded once a single-molecule contact has been formed. By comparing these curves with the single level model, we can extract the energy of the molecular level and its level broadening. This shows clearly that a single molecule is switched in situ to the on-state. The conductance of the on-state can be tuned by varying the molecular structure. These are important steps in the development of functional molecular junctions.

References 1. 2. 3.

Zotti, L. A. et al. Revealing the Role of Anchoring Groups in the Electrical Conduction Through Single-Molecule Junctions. Small 6, 1529 (2010). Sendler, T., et al. Light-Induced Switching of Tunable Single-Molecule Junctions. Advanced Science 2015, 1500017. Kim, Y. et al. Charge Transport Characteristics of Diarylethene Photoswitching Single-Molecule Junctions. Nano Lett 12, 3736 (2012).

Figures

Density controllable graphene aerogel for enhanced supercapacitor performance Dongkyun Seo, Wonji Jung, Yong Hyup Kim Seoul National University, Sillim-dong, Seoul, 151-744, Republic of Korea crew101@snu.ac.kr Abstract As reported other articles, graphene hydrogel or aerogel could be fabricated using the hydrothermal synthesis[1]. However, the fabricated graphene structure is composed by randomly aligned graphene and many pores. And utilizing this conventional synthesis method, the density and specific surface area could not be controlled. In this article, we could fabricate density controllable graphene structure. Using various concentration and quantity of graphene oxide solution, graphene structures which have controllable densities of 10~35 mg/cm3 and BET surface area could be fabricated. Also, fabricated structure could be controlled of mechanical and electrical characteristics. Because the fabricated graphene structure contains plenty of micro-pores, it is applied to an electrode of supercapacitor. As the elastic structure could control the porosity and pore density, the supercapacitor performance could be adjusted by graphene hydrogel electrode. References [1] Yuxi Xu, kaixuan Sheng, Chun Li and Gaoquan Shi, ACS Nano, 4 (2010) 4324. Figures

Photochemical Metallic Conduction Channel Creation in InGaZnO by H Radical Doping Hyungtak Seo, Myung-Ho Kim, Young-Ahn Lee, Jinseo Kim, Duck-Kyun Choi Department of Energy Systems Research, Ajou University, Suwon 405, Republic of Korea Contact@E-mail: hseo@ajou.ac.kr Abstract The photochemical tunability of charge transport mechanism in metal-oxide semiconductors is of great interest since it may offer a facile but effective semiconductor-to-metal transition, which results from photochemically modified electronic structure for various oxide-based device applications.[1,2] This might provide a feasible hydrogen (H)-radical doping to realize the effectively H-doped metal oxides [3], which has not been achieved by thermal and ion-implantation technique in a reliable and controllable way.[4] In this study, we report a photochemical conversion of InGaZnO (IGZO) semiconductor to a transparent conductor via hydrogen doping to the local nanocrystallites formed at the IGZO/glass interface at room temperature (RT). In contrast to thermal or ionic hydrogen doping, ultraviolet exposure of the a-IGZO surface promotes a photochemical reaction with H radical incorporation to surface metal± OH layer formation and bulk H-doping which acts as a tunable and stable highly doped n-type doping channel and turns a-IGZO to a transparent conductor. This results in the total conversion of carrier conduction property to the level of metallic conduction with sheet resistance of ~16 ȍ Ƒ, RT hall mobility 2 -1 -1 20 -3 of 11.8 cm V sec , the carrier concentration at ~10 cm without any loss of optical transparency. We demonstrated successful applications of photochemically highly n-doped metal oxide via optical dose control to transparent conductor with excellent chemical and optical doping-effect stability. References [1] W. Meevasana, P. D. C. King, R. H. He, S. K. Mo, M. Hashimoto, A. Tamai, P. Songsiriritthigul, F. Baumberger, and Z. X. Shen, Nat. Mater. 10 (2), (2011) 114. [2] S. Ohkoshi, Y. Tsunobuchi, T.i Matsuda, K. Hashimoto, A. Namai, F.i Hakoe, and H. Tokoro, Nat Chem 2 (7), (2010) 539. [3] A. Janotti and C. G. Van de Walle, Nat Mater 6 (1), (2007) 44. [4] K. Nomura, T. Kamiya, and H. Hosono, ECS Journal of Solid State Science and Technology 2 (1), (2013) 5. Figures

cc10 10 10

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a-IGZO nc-IGZO region region

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GaO C InO ZnO

H at surface 3

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10 10

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100 a-IGZO region

200 nc-IGZO region

300 Glass substrate

O Si

H 5

SiO

H at Surface

GaO C InO ZnO

0 3 6 9 12 15 18

100

200

300

400

Sputter Time (sec)

Morphology of IGZO film the modified electronic structure for H-doped local nanocrystallites by doping activation. (a) Cross-sectional HR-TEM images, (b) OK1 edge STEM-EELS spectra, (c) TOFSIMS depth profile of (top) the as-deposited and (bottom) UV-exposed IGZO films on the glass substrate.

Effective and Stable H doping in ZnO by Photochemical Radical Insertion *

Hyungtak Seo , Ayoung Park, Sangyeon Lee, Gowoon Shim, and Jinseo Kim Department of Energy Systems Research, Ajou University, Suwon 405, Republic of Korea Contact@E-mail: hseo@ajou.ac.kr Abstract Among many metal oxides, ZnO has various advantages such as low manufacturing cost, relatively stable surfaces, and great tunability of surface conductivity by post anneal process. Furthermore, the highly conductive ZnO can be applied to the transparent electrode in the visible light region due to its ultraviolet range band gap. Absorption or emission of light in the wide photon range from the blue region to the ultraviolet region of ZnO are possible is ideal for a broad light-emitting diodes, optical filters, optical detectors, and solar cells. In spite of these merits of ZnO, the application of ZnO as the transparent electrode still requires improved electrical conductivity without transparency degradation. In this study, ZnO surface electronic structure was modified by annealing in vacuum and exposing to UV light which improves the surface conductivity of ZnO. From experimental results, we confirmed that the annealed ZnO thin film is polycrystalline. The exposure of UV light to ZnO in air led to the surface OH bond formation by photochemical H incorporation by the adsorbed water dissociation and forming Ovacancy sites in ZnO. This is believed to act as strong n-type donor providing excess conduction electrons in ZnO surface and bulk. The modified electronic structure of UV-exposed ZnO did not affect the visible light absorption and transparency. Regardless of the initial resistivity of ZnO samples prepared by varying RF sputtering conditions, the electrical conductivity was improved by up to x1000. As a consequence, it was found that, the H doping is more effective for the annealed samples compared to un-annealed one. The preliminary physical mechanism is also suggested to explain the origin of photochemical tunability of ZnO by UV photochemistry. References 1) C. G. Van de Walle, Physical Review Letters, 85, 1012 (2000) 2) Anderson Janotti and Chris G. Van De Walle, Nature Materials, 6, 44 (2007). Figures

Analysis of Hydrogen doped ZnO by the UV treatment (a) I-V spectroscopy graph, (b) TOF-SIMS depth profile of ZnO film samples on the SiO2 substrate, (c) Cross-sectional HR-TEM images, (d) OK1 edge STEM-EELS spectra.

Wire grid polarizer basing on interband absorption in the deep ultra violet spectral range Thomas Siefke, Dennis Lehr, Daniel Voigt, Stefanie Kroker, Ernst-Bernhard Kley and Andreas TĂźnnermann Institute of Applied Physics, Friedrich-Schiller-University Jena, Albert-Einstein-StraĂ&#x;e 15, 07745 Jena, Germany Thomas.Siefke@uni-jena.de Abstract

Polarizers are essential optical elements, utilized in numerous optical applications. Such components can be realized as nano-optical wire grid polarizers (WGP). These are zero order gratings offering an anisotropic transmittance depending on the direction of the electric field vector of the incident light. Wire grid polarizers are superior to other polarizer concepts due to their large possible free aperture (up to several 100 mm) while being simultaneously extremely thin (about 0.5 mm). Furthermore, they offer very large acceptance angle, and integration in other optical elements as masks for lithography or imaging sensors is easily possible. This has already enabled many previously unprecedented optical devices. In future such applications will advance further into the deep ultraviolet region. Currently, wire grid polarizer are made of metals as aluminum. This, fundamentally, becomes inefficient at short wavelengths leading to a virtual application limit at about 250 nm. In this contribution we propose wire grid polarizer basing on interband transitions in semiconductors to expand their application range. Interband transitions are linked to pronounced absorption. Therefrom, an effective damping of the undesired polarization direction can be achieved. Depending on the actual material, these transitions occur in the DUV wavelength range. This renders such materials as superior candidates for the fabrication of DUV wire grid polarizers. In addition to the material requirements, the structure parameters of such elements are crucial for the optical functionality. A purposeful optical performance necessitates periods smaller than 100 nm (see fig. 1), ridge heights of about 150 nm and fill factors of about 25%. We successfully demonstrate the fabrication process by exploiting very fast character projection electron beam lithography and a double patterning process. Thereby, large DUV wire grid polarizers with a size of 100mm x 100mm were fabricated. At a wavelength of 270 nm the measured extinction ratio of such elements is larger than 500 and the transmittance is above 40% (see fig 2). The application wavelength ranges from about 230 nm to 290 nm. In this contribution we will discuss both, design and fabrication aspects of these nano-optical wire grid polarizers.

Extinction Ratio

Figures 600 500 400 300 200 100 0

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100 75 50 25 0 200

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300 350 400 450 Wavelength / nm Fig. 2: Measured optical properties of a DUV wire grid polarizer basing on interband absorption

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Modification of the Photonic Properties of Cyanine Thin Films by Near Fields of Plasmonic Nanostructures Anton Starovoytov, Nikita Toropov, Rezida Nabiullina ITMO University, 49 Kronverksky Pr., St. Petersburg, Russia Anton.Starovoytov@gmail.com Excitation of the surface plasmons localized in the metal nanoparticles are known to lead to the huge enhancement of their near fields. This property is well documented in the current theoretical papers. Enhancement of the field contributes to the well-known surface enhanced Raman scattering (SERS), which is the basis of novel chemical and biological sensors. One of exotic applications is the first in the world nanolaser based on gold nanoparticles and dye molecules. Thus it is known that the presence of the noble metal nanoparticles can modify the photonic properties of the solutions of organic dyes. But the solid-state structures of organic molecules and metal nanoparticles are needed in the majority of applications. For example it can be used for developing the thin-film solar cells and the OLED-displays. This scientific and technological direction is novel because the first papers about such solar cells and OLEDs based on plasmonic nanostructure were published only in last 2â&#x20AC;&#x201C;3 year. Despite the studies that have been carried out, the mechanism of the changes in absorption and fluorescence spectra has not been definitively explained. The situation with ensembles of metallic nanoparticles formed on the surface of transparent dielectric substrate during physical thermal deposition is especially complex. Because of the relative simplicity, this method of producing plasmonic nanoparticles is useful for applications. At the same time, it has such disadvantages as significant variation in the shape of the produced nanoparticles. An additional difficulty in interpreting the results of experiments with organic thin films on dielectric substrates is the broadening of the absorption spectra of dye film in comparison with dye solutions is due to formation of different molecular forms, even when there are no metallic nanoparticles on the substrate. So we studied the dependence of the fluorescence enhancement of organic molecules in the near field of plasmon nanoparticles. , and also on the distance between the components was studied experimentally. Therefore we studied the influence of metallic nanoparticles on the absorption and fluorescence of molecular forms formed in hybrid planar nanostructures. Also the dependence of the photonic properties were experimentally determined depending on the distance between the molecules and particles.

Topography-Controlled Alignment of DNA Origami Nanotubes on Nanopatterned Surfaces 1 Bezu Teschome , Stefan Facsko , Adrian Keller 1

Institute of Ion Beam Physics and Materials Research, Forschungszentrum Dresden-Rossendorf, Bautzner LandstraĂ&#x;e 400, 01328 Dresden, Germany. 2 Technical and Macromolecular Chemistry, University of Paderborn, Warburger Str. 100, 33098 Paderborn, Germany. b.teschome@hzdr.de

Abstract Since its discovery, DNA origami technique [1] has attracted considerable attention from various research fields. By this technique, it has become possible to generate complex 2D and 3D DNA nanostructures with any desired shape. Quasi-one dimensional DNA nanostructures hold particularly great promise as scaffolds for nanoelectronic device fabrication. However, the fabrication of functional nanoelectronic devices from such DNA nanostructure templates requires their controlled arrangement and orientation on a conventional substrate. In the past, various techniques have been employed to control the alignment of immobilized DNA nanostructures on different surfaces [2], [3]. However, most techniques rely on lithographic pre-patterning and often also a chemical functionalization of the substrate. In this work, we demonstrate a compelling alternative approach to generate ordered arrays of DNA nanotubes on topographically patterned surfaces. To this end, we combine two bottom-up techniques for nanostructure fabrication, i.e., DNA origami self-assembly and self-organized nanopattern formation on silicon surfaces during ion sputtering [4], thus avoiding the necessity of lithographic processing or chemical modifications. The self-alignment of the six-helix-bundle (6HB) DNA origami nanotubes is purely driven by electrostatic interactions with the nanorippled Si/SiO2 surface during adsorption. By tuning the pattern dimensions to match the dimensions of the DNA origami nanotubes, we obtain an alignment yield of 70% [5]. References [1] P. W. K 5RWKHPXQG Âł)ROGLQJ '1$ WR FUHDWH QDQRVFDOH VKDSHV DQG SDWWHUQV Â´ 1DWXUH YRO QR 7082, pp. 297Âą302, Mar. 2006. [2] $ ( *HUGRQ 6 6 2K . +VLHK < .H + <DQ DQG + 7 6RK Âł&RQWUROOHG GHOLYHU\ RI '1$ RULJDPL RQ SDWWHUQHG VXUIDFHV Â´ 6PDOO :Hinh. Bergstr. Ger., vol. 5, no. 17, pp. 1942Âą1946, Sep. 2009. [3] R. J. Kershner, L. D. Bozano, C. M. Micheel, A. M. Hung, A. R. Fornof, J. N. Cha, C. T. Rettner, M. %HUVDQL - )URPPHU 3 : . 5RWKHPXQG DQG * 0 :DOOUDII Âł3ODFHPHQW DQG RULHQWDWLRQ RI individual '1$ VKDSHV RQ OLWKRJUDSKLFDOO\ SDWWHUQHG VXUIDFHV Â´ 1DW 1DQRWHFKQRO YRO QR SS Âą561, Sep. 2009. [4] $ .HOOHU DQG 6 )DFVNR Âł,RQ-Induced Nanoscale Ripple Patterns on Si Surfaces: Theory and ([SHULPHQW Â´ 0DWHULDOV YRO QR pp. 4811Âą4841, Oct. 2010. [5] % 7HVKRPH 6 )DFVNR DQG $ .HOOHU Âł7RSRJUDSK\-controlled alignment of DNA origami nanotubes RQ QDQRSDWWHUQHG VXUIDFHV Â´ 1DQRVFDOH YRO QR SS Âą1796, Jan. 2014.

Prevention of bacterial adhesion onto electrospun fibroporous poly(carbonate) urethane membrane by embedding Graphene oxide Sudhin Thampi

a, b

, Maya Nandkumar , Ramesh Parameswaran , Vignesh Muthuvijayan ,

Indian Institute of Technology Madras, Chennai-600036, Tamil Nadu.,India Sree Chitra Tirunal Institute of Medical Sciences and Technology, Biomedical Technology Wing, Poojappura, Trivandrum-695012, Kerala, India

thampisudhin2005@gmail.com Abstract Functional restoration of human body is assisted by implantation of long term simple or sophisticated medical devices which closely involves use of biomaterials. Biomaterials, in such a scenario attract lots of bacteria which colonize and infect the surrounding healthy tissue leading to severe failure and rejection of the device. Bacterial infection starts with adherence of bacteria to biomaterial device surfaces either from pre-operative or post operative environment and formation of biofilm [1]. Solution to this problem lies in the development of coatings and materials which dissuade bacteria from attaching to these surfaces. Polyurethane based elastomeric membranes have found widely acclaimed usage as implants in biomedical applications EXW GRHVQ¶W KDYH DQ\ PHFKDQLVP WR ZDUG off a bacterial invasion. To bring out such a defense mechanism we are adopting surface modification. GO (Graphene Oxide) was embedded onto the electrospun fibroporous polycarbonate urethane membrane by a simple method of electrospraying. The study represents our findings on antibacterial activity and efficiency of the method developed. Various tools like SEM, contact angle, Raman spectra and mapping, and techniques like bacterial adhesion study have been done to support the data. Bacterial adhesion study on modified surface (GPU) and unmodified surface (PU) against Staphylococcus aureus (Gram positive, cocci) (SA) showed a reduction in 85% adhesion while a 64% reduction was seen against Pseudomonas aeruginosa (Gram negative, bacilli) (PA). SEM micrographs show the attachment of bacteria to the fibroporous membrane. On GPU, contact angle got reduced from 121.5°±1.5° to 92.5°± 4.2° making the surface slightly hydrophilic while Raman spectra and mapping showed the distribution of GO over the membrane surface. References 1.

Busscher, Henk J., Henny C. van der Mei, Guruprakash Subbiahdoss, Paul C. Jutte, Jan JAM van den Dungen, Sebastian AJ Zaat, Marcus J. Schultz, and David W. Grainger. Science translational medicine, 153 (2012), 153rv10 (1-10).

Figures PU-SA

SEM micrograph of SA attached to PU

GPU-SA

SEM micrograph of SA attached to GPU

GRAPHENE PRODUCTION: &$12(¶6 5(63216( )25 ,1'8675,$/ 1(('6 Hubert THUILLIER, P. GAILLARD CANOE/ADERA, 16 avenue Pey Berland, 33600 PESSAC, FRANCE thuillier@plateforme-canoe.com Abstract: Due to the scientific interest for this material, graphene world production is growing fast. Different types of graphene, from monolayer to graphene nano platelet (GNP) are produced with 4 distinct technologies Oxidation - Reduction CVD Liquid phase exfoliation Substrate -less plasma CVD gold Nevertheless, looking at the few finished graphene based products on the market, graphenes marketed as powders or semi-finished products (liquid dispersions or masterbatches) do not fit with the industrial reality. In fact, end users need to make a compromise between the intrinsic properties and the cost of these materials. CANOE platform, a French center dedicated to nanostructured composites, has chosen to meet the industrial needs by developing a new graphene production approach by catalytic chemical vapor deposition in fluidized bed process. This technology has allowed the production of Few Layers Graphene with properties corresponding to the specifications of the end users: thickness <10 layers, high purity,%O < 1% and low cost. This production pilot, using bio based raw materials currently has a production capacity of 8 T / year. The development of this process is now integrated into the French research program ³GRAPULE´ that integrates 3 end users in the field of printed electronics, industrial coatings and aerospace, 2 academic laboratories specialized in the field of catalysis and liquid dispersions and two technology centers. The project integrates the entire value chain, from FLG production to final demonstrators through the supply of liquid dispersions or masterbatches.

Figures:

Carbon Nanotube Interconnects for Energy Efficient Integrated Circuits Aida Todri-Sanial CNRS-LIRMM/University of Montpellier, Montpellier, France todri@lirmm.fr Abstract - Carbon nanotubes (CNTs) due their unique mechanical, thermal, and electrical properties are being investigated as promising candidate material for on-chip and off-chip interconnects. The attractive mechanical properties of CNTs, including high Youngs modulus, resiliency and low thermal expansion coefficient offer great advantage for reliable and strong interconnects, and even more so for 3D integration. Through-Silicon-Vias (TSVs) enable 3D integration and implementation of denser, faster and heterogeneous circuits, which also lead to excessive power densities and elevated temperatures. Due to their unique properties, CNTs present an opportunity to address these challenges and provide solutions for reliable 3D integration. In this work, we perform detailed analyses of horizontally aligned CNTs and report on their efficiency to be exploited for 3D power delivery networks.

exploiting their unique electrical and thermal properties. In Fig. 1 the model of an individual MWCNT is shown with parasitics represent both dc conductance and high-frequency impedance i.e. inductance and capacitance effects. Multiple shells of a MWCNT are presented by their individual parasitics. Such model can also be applicable to SWCNTs where only a single shell is represented.

Introduction One essential and most interesting application of the nanotubes in microelectronics is as interconnects using the ballistic (without scattering) transport of electrons and the extremely high thermal conductivity along the tube axis. Electronic transport in SWCNTS and MWCNTS can go over long nanotube lengths, 1um, enabling CNTs to carry very high currents 9 2 (i.e. > 10 Acm ) with essentially no heating due to nearly 1D electronic structure. In literature, the comparison of copper and CNTs have been limited to signal interconnects. Investigation of CNTs for power and clock delivery would also have a significant importance. It would reveal whether or not CNTs can potentially replace both signal, and power/ground copper wires. Additionally, clock and power networks are most vulnerable to electromigration, it is therefore critical to know whether or not CNTs improve their reliability. There are many works in literature that investigate CNT interconnects. The first group of works focuses on modeling aspects of CNT interconnects [1-2]. The second group of works focuses on performance comparison of CNT interconnects versus copper (Cu) interconnects [3-4]. Almost all these works have considered the application of CNT interconnects for signaling and few works focus on power delivery [4]. Complementary to these efforts, in this work, we investigate the application of horizontally aligned CNTs for power delivery network (i.e. both 2D and 3D ICs) while

Fig.1 Electrical modeling of CNT interconnects. In Fig.2 the voltage drop on CNT interconnects due to its parasitics is plotted as a function of length and outer nanotube diameter.

Fig. 2. Voltage drop on CNT interconnect as a function of length and outer nanotube diameter. References [1] A. Naeemi, et al., ``Performance Comparison Between Carbon Nanotube and Copper Interconnects for Gigascale Integration,'' IEEE Electron Device Letter, vol.26, no.2, pp.84-86, 2005. [2] A. Naeemi, et al.,''Performance Modeling for Carbon Nanotube Interconnects in on-Chip Power Distribution,'' ECTC, pp. 420-428, 2007. [3] H. Li, et al., ``Low-Resistivity Long-Length Horizontal Carbon Nanotube Bundles for Interconnect Applicationsâ&#x20AC;&#x201D; Part II: Characterization,'' IEEE Trans. Electron Devices, vol.60, no.9, pp.2870-2876, 2013. [4] N.H. Khan, et al, ``The Feasibility of Carbon Nanotubes for Power Delivery in 3D Integrated Circuits,'' ASP-DAC, pp.53-58, 2012.

Thin films of organic dyes with silver nanoparticles: enhancement and spectral shifting of fluorescence due to excitation of localized surface plasmons Nikita A. Toropov, Aisylu N. Kamalieva, Tigran A. Vartanyan ITMO University, 197101 Kronverkskiy pr. 49, St. Petersburg, Russia nikita.a.toropov@gmail.com Abstract Organic dyes molecules are attractive objects of investigation due to their bright optical properties and wide range of applications in generation of coherent radiation, photodynamic cancer therapy, visualization etc. At the same time, optical properties of very thin dye layers that play an important role in the modern technogies, are studied insufficiently. In the layers of nanometer thickness dye molecules, often demonstrate such unwanted properties as reduced absorption, fluorescence quenching and changes of their spectra due to isomerization and aggregation [1]. In this contribution, we propose and demonstrate how silver nanoparticles may be used for enhancement of absorption and fluorescence of organic dye thin films. Our proposal is based on the fact that silver nanoparticles possess localized surface plasmon resonances that lead to the huge enhancement of the electric fields around them. In the experiments, silver nanoparticles were vacuum-deposited on the quartz substrates and washed in the organic dye solvent for stabilization of their morphology. After that, optical density of nanoparticles in the vis-NIR spectral region was measured. The samples obtained in this way allow us to study interactions of silver nanoparticles with different organic thin films because they have wide absorption bands (400Âą900 nm). In this work we studied the influence of local fields of nanoparticles on three organic dyes with different maxima of absorption: malachite green with absorption peak at 618 nm in ethanol solution. rhodamine and coumarin with absorption peaks at 530 nm and 403 nm, correspondingly. Dyes were spin-coated on the surface and dried at ambient conditions. It is known that the influence of metallic surfaces on the dye molecules is two-fold. On one hand, they contribute to the quenching of molecular excitation. On the other hand, the enhanced near fields at the metal surfaces and Purcell effect lead to the enhancement of the fluorescence. To get the most of the enhancement factors and at the same time to avoid quenching, we propose to use poly(methyl methacrylate) as a matrix that keeps the organic molecules at the optimum distance from the metal surface. Optical density spectra of organic dye doped PMMA films were enhanced in the presence of silver nanoparticles (fig. 1). Experimental investigations of the fluorescence demonstrated the 13-, 17-, and 20-fold enhancement for malachite green, rhodamine and coumarin in the presence of silver nanoparticles. Also, the fluorescence maximum is slightly shifted (about 10 nm) in the presence of silver nanoparticles (fig. 2). References [1] Toropov N.A., Parfenov P.S., Vartanyan T.A., J. Phys. Chem. C, 118 (2014) 18010Âą18014. Figures 1000

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Magnetic nanocomposites based on mesoporous silica for biomedical applications Z. Vargas1, Y. Piñeiro1, C. Vazquez-Vazquez2, C. Rodríguez3, M.A. López-Quintela2 and J. Rivas1 1

Dept. Física Aplicada, 2 Dept. Química Física, Universidad de Santiago de Compostela, E-15782, Santiago de Compostela, España. 3 International Nanotechnology Laboratory (INL), Avda. Mestre José Veiga s/n, 4715, Braga, Portugal voz_wolverine74@hotmail.com, jose.rivas@usc.es

Abstract: Multifunctional nanocarriers, integrating diagnostic and therapeutic functions, have attracted increasing scientific attention recently. Magnetic-mesoporous silica nanocomposite materials are emerging as one of the most appealing candidates to produce novel nanodevices[1] for personalized medicine, theranostic carriers, celular and diagnostic MRI in vivo, magnetofection, hyperthermia, magnetic bioseparation, molecular diagnostics, magnetic-controlled drug release systems and osseous regeneration devices[2,3]. The main driving force for this trend is connected to the possibility of combining synergistic magnetic, mesoporous, and biological entities and functions in a well-defined host matrix[1], also looking for tissue engineering constructs capable of combining the replacement of damaged parts with local cancer treatment[2]. The synthesis of mesoporous silica materials with controlled physicochemical characteristics like large pore volume, high surface area, narrow pore size distribution, tunable pore size and high hydrothermal stability, is of large interest due to its inert, harmless, and inexpensive character and their ever-expanding list of applications [4]. The incorporation of magnetic nanoparticles (MNPs) into these biocompatible mesoporous scaffold formulations [5,6] provides final materials with additional magnetic functionality and reinforced mechanical properties for bone tissue engineering applications. Magnetic functionality comprise different beneficial effects like magnetic stimulation on biological media (i.e., enhancement of cell adhesion/proliferation), guiding of growth factors loaded magnetic nanocarriers[7],or the in vivo localized heat release by magnetic hyperthermia with the help of an externally applied alternating magnetic field[8]. So the aim of this study was conducted by the synthesis, the structural and physicochemical characterization and the applications as scaffolds for bone tissue engineering and soft and hard hyperthermia devices for cancer treatment of magnetic-mesoporous silica nanocomposite materials. In the present work we report the synthesis procedure of magnetic mesoporous SBA-15 ceramics with controlled morphology. Different procedures and synthetic parameters are varied in order to control the physico-chemical, textural and magnetic properties of these materials. Our results show that magnetic mesoporous silica presents a flat two-dimensional hexagonal symmetry with the presence of mesoporous ordination cylindrical geometries, opened at both ends, with magnetite nanoparticles anchored on their surface and in the channels as shown by TEM and SEM micrographs 2 (figure 1). Measured by BET, these materials show a surface area above 250 m /g, which assures a higher ability to be loaded with different molecules than conventional ceramics. The presence of crystalline magnetite is corroborated by the XRD spectra (figure 2) which reveals the typical iron oxide crystalline pattern peaks. In the figure two, spectra are presented corresponding to samples with low (bottom spectra) and high (top spectra) amounts of magnetite in the ceramic. Magnetic characterization was performed with a vibrating sample magnetometer (VSM), where field dependent magnetization cycles were performed at room temperature for two samples (with low and high magnetite content) and results are presented in figure 3. The magnetization cycles show no hysteresis or coercive forces, which is highly desirable for biomedical applications to avoid magnetic agglomeration of particles. In addition hyperthermia characterizations have been performed to assess the magneto-thermal abilities of two representative samples. The hyperthermia response can be tuned by varying the content of magnetite as evidenced in figure 4, where negligible temperature increase (low magnetite content) or a high increase of about 40º C in only one minute (high magnetite content) can be obtained depending on the physicochemical properties of the ceramic and the magnetite content. This tunable response can be an advantage for different tissue engineering purposes since it allows for magnetic enhancement of bone cell growth and differentiation (low thermal increase) or locally killing cancer cells (high thermal increase) with magnetic hyperthermia by selecting the proper magnetite doping. In addition the porous character of SBA-15 ceramics allows to functionalize the material with growth factors, specific antibiotics or therapeutic drugs to promote regeneration and healing in bone diseases. In summary, magnetic mesoporous SBA-15 ceramics have been synthesized by different routes and varying chemical parameters to obtain tunable physicochemical, morphological and magnetic properties suitable for different biomedical applications.

References [1] Zhang, Jixi et al. Journal of Colloid and Interface Science 361.1 (2011): 16±24. [2] Vallet-Regí, María, and Eduardo Ruiz-Hernández. Advanced Materials 23.44 (2011): 5177±5218. [3] Rosenholm, Jessica M. et al. Microporous and Mesoporous Materials 145.1-3 (2011): 14±20. [4] Nandiyanto, Asep Bayu Dani et al. Microporous and Mesoporous Materials 120.3 (2009): 447±453. [5] Vallet-Regí, María, Montserrat Colilla, and Blanca González. Chemical Society reviews 40.2 (2011): 596±607. [6] Fuertes, Antonio B., Patricia Valle-Vigón, and Marta Sevilla. Journal of Colloid and Interface Science 349.1 (2010): 173±180. [7] Bañobre-López, Manuel et al. IEEE Transactions on Magnetics, 50. 11 (2014) [8] Sousa, Andreza De et al. Journal of Nanomaterials 2014 (2014): ID 293624

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mesoporous Silica & Fe3O4 (NC)

mesoporous Silica & Fe3O4 (NC): 60

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20 0,0

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High field magneto-transport in Graphene Grown by Chemical Vapor Deposition on SiC 1

M. Yang , O. Couturaud , W. Desrat , D. Kazazis , A. Michon 1 1 1 2 M. Pierre and M. Goiran , W. Escoffier and B. Jouault

Laboratoire National des champs Magnétiques Intenses, UPR 3228 CNRS-Université de Toulouse, France 2 Laboratoire Charles Coulomb, UMR 5221 CNRS-Université de Montpellier, France 3 Laboratoire de Photonique et de Nanostructures, UPR 20 CNRS, France 4 Centre de Recherche sur l'Hétéro-Epitaxie et ses Applications, UPR 10 CNRS, France *E-mail: ming.yang@lncmi.cnrs.fr [1]

We investigate on the transport properties of graphene on silicon carbide (SiC) in the quantum Hall regime. The longitudinal and Hall resistances have been measured of up to 67T in a temperature range between 1.6K and 120K. For low carrier densities, we observe a broad plateau of the Hall resistance at Rxy=h/2e², spanning from B=7T to B=67T (and up to 80T in a separate experiment). In the usual QHE model, the width of the quantized Hall plateaus depends on the ratio between localized and extended states. However, the very broad magnetic field range over which the Hall resistance plateau at filling factor v=2 is established cannot be explained within this usual picture. Following the lines of [2-4] reference , a charge transfer between the SiC donor states and graphene could be a possible route to explain the very large width of the last Rxy plateau. Nevertheless, this model neglects the effects of the internal Landau level structure due to disorder and predicts a fixed charge carrier density above a moderate magnetic field. Such a prediction is not consistent with our new experimental observations at very high magnetic field. On the contrary, we believe that both the effect of charge transfer and the nature of the disorder must be considered in order to explain the peculiar QHE in graphene on SiC. At very high magnetic field, the temperature evolution of the longitudinal resistance is analyzed within the framework of Variable Range Hopping describing the onset of a localization-delocalization transition. The extracted critical exponent is in agreement with a quantum percolation plateau-plateau transition when the Fermi energy approaches extended sates. This observation points towards a possible spin and valley degeneracy lifting of the N=0 Landau level at high magnetic field. Unexpectedly, we also observe faint but reproducible Shubnikov-de Haas oscillations of the longitudinal resistance for B>20T. Although the origin of these oscillations is still unclear at the moment, we believe they originate from non-homogeneous doping of the sample during device fabrication. [1] B. Jabakhanji et. al. Phys. Rev. B 89, 085422 (2014) [2] S. Kopylov et. al. Appl. Phys. Lett. 97, 112109 (2010) [3] T. J. B. M. Janssen et. al. Phys. Rev. B 83, 233402 (2011) [4] C. Chua et. al. Nano Letters 14, 3369 (2014) Longitudinal (RXX) and Hall (RXY) Resistance 14

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Quantum chemical calculations Synthesis and corrosion inhibition efficiency of ethoxylated -[2(2-{2-[2-(2-Benzenesulfonylamino-ethylamino)-ethylamino]-ethylamino}-ethylamino)-ethyl]-4alkyl-benzenesulfonamide on API X65 steel surface under H2S environment *,

E. G. Zaki M. A. Migahed , A. M. Al-Sabagh, E.A. Khamis Egyptian petroleum Research Institute, Nasr City, Cairo (11727), Egypt corresponding author: chemparadise17@yahoo.com Abstract Inhibition effect of four novel nonionic surfactants based on sulphonamide X 65 type carbon steel in oil wells formation water under H2S environment was investigated by electrochemical measurements. Scanning electron microscopy (SEM) and energy dispersion X-ray (EDX) were used to characterize the steel surface. The results showed that these surfactants act as a corrosion inhibitor in and their inhibition efficiencies depend to the ethylene oxide content in the system. The obtained results showed that the percentage inhibitioQ HIILFLHQF\ Č&#x2DC; ZDV LQFUHDVHG E\ LQFUHDVLQJ WKH LQKLELWRU FRQFHQWUDWLRQ until the critical micelle concentration (CMC) reached The quantum chemistry calculations were carried out to study the molecular geometry and electronic structure of obtained derivatives. The energy gap between the highest occupied molecular orbital and lowest unoccupied molecular orbital has been calculated using the theoretical computations to reflect the chemical reactivity and kinetic stability of compounds(1,2) [1] I. Ahamad, M.A. Quraishi, Corros. Sci. 51 (2009) 2006. [2] Ebenso, E. E.; Arslan, T.; Kandem, K.; Love, I.; Retlr, C.; Lu, M. S. and Umoren, S. A, International Journal of Quantum Chemistry, 110 (2010) 2614Âą2636. Figures

Molecular electrostatic potential map of the compound IV.

Adsorption of 4-(4"-bromophenyl)- ¶-pyridyle) benzene molecules on Si (111)-B and Cu (111) Gaolei ZHAN, Younes Makoudi, Judicael Jeannoutot Simon Lamare, Frank Palmino and Frederic Cherioux Institute FEMTO-ST, Université de Franche-Comté, CNRS, UBFC, Besançon, France gaolei.zhan@femto-st.fr Abstract The Halogen bond (XB) proves to be one of the most attractive noncovalent interactions for the formation of a 2D network on surfaces [1]. Herein, we investigate the adsorption of molecule 4-(4"bromophenyl)- ¶-pyridyle) benzene (NBR) on semiconductor and metallic surfaces. This molecule is based on p-biphenyl core ending on one side with a bromine atom and at the opposite side, with a pyridyl moiety. The pyridyl group is a Lewis base which can be involved in XB [3]. Then, NBR molecules are deposited on Si(111)-B and Cu(111) surface, respectively at room temperature. The characterizations are achieved by means of scanning tunnel microscopy under ultra-high vacuum (UHVSTM) at variable temperature. The deposition of NBR on a Si(111)-B surface (Figure 1a) displays a 2D network, while we obtained a linear nanostructure on a Cu(111) nanostructure at RT (Figure 1b). After a thermal annealing of the nanolines obtained on Cu(111), straight and disordered structures are observed (Figure 1c). On Si(111)-B, XB and pi-pi stacking interaction are the driving force of the 2D self-assembly. While on Cu(111), the Cu atoms coming from the surface are coordinated between Nitrogen atoms of two adjacent pyridyls groups (N-Cu-N bridges) and also between two carbon atoms (C-Cu-C bridges). [2]. These two types of bridge lead to the formation of organometallic nanolines. After a thermal annealing, the Cu atoms of C-Cu-C bridges are removed to obtain C-C bonds due to the Ullmann process. [2]. This work demonstrates the role of the surface to promote the formation of assemblies on surfaces. XB seems to be a convenient way to reach supramolecular 2D self-assemblies on silicon surfaces. On Cu(111), adsorption of NBR molecules leads to the formation of nanolines by metal coordination chemistry. References [1] A. Priimagi, G. Cavallo, P. Metrangolo and G. Resnati, Acc. Chem. Res.,2013, 46, 2686. [2] Wang, W., Shi, X., Wang, S., Van Hove, M. A., & Lin, N. Journal of the American Chemical Society, 2011, 133(34), 13264-13267. [3] Shirman, T., Lamere, J. F., Shimon, L. J., Gupta, T., Martin, J. M., & van der Boom, M. E. Crystal Growth and Design, 2008, 8(8), 3066-3072. Figures 1 a)

Figure 1. STM topographs of 4-(4"-bromophenyl)- ¶-pyridyl)benzene on (a) Si (111)-B and (b, c) Cu(111). All STM images were obtained at 100K with the same scale of 20nm x 20nm. a) shows 2D nanostructures obtained after molecule deposition on a Si(111)-B surface; b) Linear nanostructures obtained after molecule deposition on the Cu(111) surface at RT; c) Nanolines obtained after a thermal annealing of the linear nanostructures observed in (b). STM tunneling parameters: (a) It= 10pA, Vt= 1.6V; (b) It= 200pA, Vt= -1.6V; (c) It= 90pA, Vt=-1.8V

Research challenges, future trends and limitations in modeling and simulation of electrospun carbon nanofibers M. ZIAEI, S.RAFIEI, A. K. HAGHI University Of Guilan, Department of Textile Engineering, Rasht, Iran ziaei_m777@yahoo.com Abstract Electrospinning is an efficient and versatile technique which has been attracted great attention in current decades because of providing the nearly simple, easy and low cost to produce nanofibers from polymers or composites. During the recent years some attempts have been made to optimize the uncontrollable electrospinning process in order to create more uniform nanofibers. Modeling and simulation are suitable methods to obtain this approach. In this paper, activated carbon nanofibers were produced during electrospinning of polyacrylonitrile solution, stabilization, carbonization and activation of electrospun nanofibers in optimized conditions, and then mathematical modeling of electrosinning process will be done by focusing on governing equations of electrified fluid jet motion by using FeniCS software. Experimental and theoretical results will be compared with each other in order to estimate the accuracy of the model. The simulation can provide the possibility of predicting essential parameters which affect the electrospinning process. References [1] Teo, W, and S. Ramakrishna, Nanotechnology, 14 (2006) R89. [2] G. W. M. Peters, M. A. Hulsen, and R. H. M. Solberg, Department Of Mechanical Engineering, Eindhoven University Of Technology, (2007) 26. [3] C. J. Thompson, G. G. Chase, A. L. Yarin and D. H. Reneker, Polymer, 23 (2007) 6913-6922. [4] S. Rafiei, et al, Cellul Chem Technol, 47 (2013) 323-38. Figures

(a) Schematic diagram of electrospinning showing details of the jetting processes, the whipping instability, as well as the fiber morphologies that can be obtained. The flow rate (Q), the voltage (V) and the distance between the electrodes (dg) are set and the current (I) flowing through the jet is measured. The electric field strength is calculated as V/dg. The quantity Ć&#x2014; =I/Q) is the volumetric charge density. The photograph on the left hand side shows the straight section of the steady jet immediately after it ejects from the conical meniscus. The photograph on the right shows the whipping instability, where the centerline of the jet bends at a characteristic wavelength. The micrographs (b) and (c) show electrospun polyacrylonitrile nanofibers in optimized conditions (in different voltages). (b): concentration (11wt SXPSLQJ UDWH Č?O PLQ VSLQQLQJ GLVWDQFH FP YROWDJH (18kv) (c): concentration (11wt % SXPSLQJ UDWH Č?O PLQ VSLQQLQJ GLVWDQFH FP voltage (16kv)

Laurent Baraton

Iñigo Charola

Engie CRIGEN, France

Graphenea, Spain

Julio Gómez

Samson Patole

Avanzare, Spain

Tata Steel, UK

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