Ομάδα Έξυπνων Λειτουργικών Υλικών

Center of Materials Technology and Photonics Smart Functional Materials group www.cematep.teicrete.gr School of Engineering Technological Educational Institute of Crete

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Technological Educational Institute of Crete (TEIC) is a University of Applied Sciences located at Crete, providing education, training and research in the fields of applied technology, agricultural technology, health services and economics. The School of Engineering of TEIC is focused in the fields of Electrical, Mechanical and Civil Engineering, as well as Applied Informatics.

The Center of Materials Technology and Photonics (CEMATEP) is a joined laboratory of the departments of the School of Engineering and is dedicated to the growth, study and application of novel technological materials and photonics technology. Regarding the smart functional materials group, the research efforts are focused on the exploitation of advanced thin films, nanostructures and nanocomposites suitable for applications like solar control coatings, supercapacitors, photo-catalysis electrocatalysis, optoelectronics, HV insulators and dialectics in electrical systems. CEMATEP is well equipped with state of the art setups and its members can present very important scientific outcome as well as excellent national and international collaborations.

Personnel.

Staff from TEI of Crete Professor N. Katsarakis Professor E. Koudoumas Professor K. Savvakis Dr D. Vernardou Dr S. Dokianakis Dr I. Georgaki Dr M. Suchea, External Collaborators Prof. S. Couris, University of Patras Prof. M. Vamvakaki, University of Crete Prof. G. Kiriakidis, University of Crete Prof. Y. Raptis, National Technical University of Athens Prof. M. Pemble, Tyndall Instiute, Cork Ireland Dr D. Davazoglou, National Centre for Scientific Research "Demokritos" Dr P. Loukakos, Foundation for Research and Technology-Hellas Dr G. Kenanakis, Foundation for Research and Technology-Hellas Dr E Spanakis, University of Crete Dr Z. Viskadourakis, Foundation for Research and Technology-Hellas

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Objectives.  Use of simple, low cost and environmental friendly techniques for the growth of thin films, nanostructure layers and nanomaterials, based on pure or doped metal oxides, exhibiting properties suitable for applications in energy and environment. In particular, the functionality of nanomaterials and nanostructured composites is examined regarding applications like solar control coatings, photo-catalytic / electrocatalytic layers, transparent electrodes, self cleaning windows, optoelectronic devices, super capacitors, electromagnetic confinement etc  Investigation of the performance of carbon allotropes such as those of the graphene family, in applications like transparent electrodes, photo-catalysis / electrocatalysis and supercapacitors  Investigation of the performance of polymer based outdoor insulators used in high voltage applications Scientific achievements 1. Low temperature growth of amorphous electroactive WO 3 and V2O5, crystalline β-V2O5 and V6O13 structures suitable for the fabrication of solar control coatings, super capacitors and Li batteries.

2. Low temperature growth of metal oxide nano/microstructures (ZnO, TiO2, V2O5 and WO3) exhibiting significant photocatalytic action suitable for the degradation of gas and liquid pollutants 3. Effectual replacement of ITO in solar cells with transparent conductive layers of carbon allotropes or other metal oxide layers 4. Growth of thermochromic V1-xWxO2 layers with low transition temperature, suitable for energy saving in buildings 5. Growth of electrochromic WO3 layers with fast time response and high coloration efficiency.

6. Development of graphene based paint like layers suitable for electromagnetic confinement Implementation and Participation in projects currently implemented 1. Smart and low cost thermochromic windows for energy saving in buildings, Cooperation project funded by Greece 2. Investigation of the performance of polymer based outdoor insulators used in high voltage applications and development of a remote and real-time diagnostic technique for the evaluation of their functionality, Cooperation project funded by Greece 3. Nanostructured metal oxide photocatalysts, Archimedes III project, funded by Greece 4. Growth and characterization of novel nanostructured layers suitable for the confinement of GHz electromagnetic radiation, Archimedes III project, funded by Greece 5. Electrochromic, low cost, advanced windows, Archimedes III project, funded by Greece Available facilities Α) Deposition/Processing  Atmospheric Pressure Chemical Vapor Deposition setup (APCVD)  Spray and Ultrasonic Spray Pyrolysis setups

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 Setup for solution growth  Setup for sol-gel growth  Agar B7367A Carbon coater  Centrifuge, Ultrasonic baths/probes, Distillation setup, Setup for preparation of MilliQ water, and various ovens for growth, drying and annealing Β) Characterization techniques  Scanning electron microscope (SEM), with Energy dispersive X-ray analysis  Shimadzu FT-IR Spectrophotometer  Shimadzu UV-VIS Spectrophotometer  Oriel Research Arc Lamp Housings Solar Simulator  Agilent B1500A Semiconductor Device Analyzer  Setup for 2-point and 4-point probe conductivity/resistivity measurements  Cyclic voltammetry  Electrochemical Impedance Spectroscopy  Van der Pauw Ecopia Hall Measurement System  Optical video contact angle system  Spectrometer  Single housing narrow bandwidth nsec OPO with pump laser system; tunable nsec laser radiation from 210-2300 nm.  Setup for the study of photocatalytic action with UV and solar simulator light  Setup for the study of thermochromic and electrochromic action  Setup for the study of the performance of electrochromic devices  Photo-electrochemical cell for the study of the performance of metal oxide and graphene based electrodes  UV lamps, optical microscopes and spectrometers Recent publications 1. Vernardou, D., Marathianou, I., Katsarakis, N., Koudoumas, E., Kazadojev, I.I., O'Brien, S., Pemble, M.E., Povey, I.M., Capacitive behavior of Ag doped V2O5 grown by aerosol assisted chemical vapour deposition (2016) Electrochimica Acta, 196, pp. 294-299.

2. Louloudakis, D., Vernardou, D., Spanakis, E., Suchea, M., Kenanakis, G., Pemble, M., Savvakis, K., Katsarakis, N., Koudoumas, E., Kiriakidis, G., Atmospheric pressure chemical vapor deposition of amorphous tungsten doped vanadium dioxide for smart window applications (2016) Advanced Materials Letters, 7 (3), pp. 192-196.

3. Liaros, N., Couris, S., Koudoumas, E., Loukakos, P.A., Ultrafast Processes in Graphene Oxide during Femtosecond Laser Excitation, (2016) Journal of Physical Chemistry C, 120 (7), pp. 4104-4111.

4. Vernardou, D., Louloudakis, D., Katsarakis, N., Koudoumas, E., Kazadojev, I.I., O'Brien, S., Pemble, M.E., Povey, I.M., Electrochemical evaluation of vanadium pentoxide coatings grown by AACVD (2015) Solar Energy Materials and Solar Cells, 143, pp. 601-605.

5. Vernardou, D., Psifis, K., Louloudakis, D., Papadimitropoulos, G., Davazoglou, D., Katsarakis, N., Koudoumas, E., Low pressure CVD of electrochromic WO3 at 400°C (2015) Journal of the Electrochemical Society, 162 (9), pp. H579-H582.

6. Psifis, K., Louloudakis, D., Vernardou, D., Spanakis, E., Papadimitropoulos, G., Davazoglou, D., Katsarakis, N., Koudoumas, E.,

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Effect of O2 flow rate on the electrochromic response of WO 3 grown by LPCVD (2015) Physica Status Solidi (C) Current Topics in Solid State Physics, 12 (7), pp. 1011-1015.

7. Suchea, M., Tudose, I.V., Tzagkarakis, G., Kenanakis, G., Katharakis, M., Drakakis, E., Koudoumas, E., Nanostructured composite layers for electromagnetic shielding in the GHz frequency range (2015) Applied Surface Science, 352, pp. 151-154.

8. Louloudakis, D., Vernardou, D., Spanakis, E., Dokianakis, S., Panagopoulou, M., Raptis, G., Aperathitis, E., Kiriakidis, G., Katsarakis, N., Koudoumas, E., Effect of O2 flow rate on the thermochromic performance of VO2 coatings grown by atmospheric pressure CVD (2015) Physica Status Solidi (C) Current Topics in Solid State Physics, 12 (7), pp. 856-860.

9. Christou, K., Louloudakis, D., Vernardou, D., Katsarakis, N., Koudoumas, E., One-pot synthesis of WO3 structures at 95 °C using HCl (2015) Journal of Sol-Gel Science and Technology, 73 (3), pp. 520526.

10. Vernardou, D., Louloudakis, D., Spanakis, E., Katsarakis, N., Koudoumas, E., Amorphous thermochromic VO2 coatings grown by APCVD at low temperatures (2015) Advanced Materials Letters, 6 (7), pp. 660-663.

11. Vernardou, D., Apostolopoulou, M., Louloudakis, D., Katsarakis, N., Koudoumas, E., Electrochemical Performance of Vanadium Oxide Coatings Grown using Atmospheric Pressure CVD (2015) Chemical Vapor Deposition. Article in Press.

12. Apostolopoulou, M., Louloudakis, D., Vernardou, D., Katsarakis, N., Koudoumas, E., Kiriakidis, G., Study of the pH effect on the properties of the hydrothermally grown V2O5 (2015) Thin Solid Films, 594, pp. 338-342.

13. Christou, K., Louloudakis, D., Vernardou, D., Savvakis, C., Katsarakis, N., Koudoumas, E., Kiriakidis, G., Effect of solution chemistry on the characteristics of hydrothermally grown WO3 for electroactive applications (2015) Thin Solid Films, 594, pp. 333-337.

14. Vamvasakis, I., Georgaki, I., Vernardou, D., Kenanakis, G., Katsarakis, N., Synthesis of WO3 catalytic powders: evaluation of photocatalytic activity under NUV/visible light irradiation and alkaline reaction pH (2015) Journal of Sol-Gel Science and Technology, 76 (1), pp. 120-128.

15. Kenanakis, G., Vernardou, D., Dalamagkas, A., Katsarakis, N., Photocatalytic and electrooxidation properties of TiO2 thin films deposited by sol-gel (2015) Catalysis Today, 240 (PA), pp. 146-152.

16. Vasilaki, E., Georgaki, I., Vernardou, D., Vamvakaki, M., Katsarakis, N., Ag-loaded TiO2/reduced graphene oxide nanocomposites for enhanced visible-light photocatalytic activity (2015) Applied Surface Science, 353, pp. 865-872.

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