IM20211EN

Volume 1 2021

BANANA FIBER PALLETS FLEXIRAMICS, FLEXIBLE CERAMIC FIBER MATERIAL TECLA 3D PRINTED EARTH HOUSE GLUE ACTIVATED BY MAGNETIC FIELD THE LOBSTER WAY: STRONGER 3D PRINTED CONCRETE LIQUID WINDOW BLUE-LIGHT PEROVSKITE-BASED LEDS

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CONTENT About

Innovatieve Materialen (Innovative Materials) is a digital, independent magazine about material innovation in the fields of engineering, construction (buildings, infrastructure and industrial) and industrial design.

A digital subscribtion in 2021 (6 editions) costs € 40,70 (excl. VAT) Members of KIVI and students: € 25,- (excl. VAT)

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Gerard van Nifterik

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Innovative Materials platform: Dr. ir. Fred Veer, prof. ir. Rob Nijsse (Glass & Transparency Research Group, TU Delft), dr. Bert van Haastrecht (M2I), prof.

Wim Poelman, dr. Ton Hurkmans (MaterialDesign), prof.dr.ir. Jos Brouwers, (Department of the Built Environment, Section Building Physics and Services TU Eindhoven), prof.dr.ir. Jilt Sietsma, (4TU.HTM/ Mechanical, Maritime and Materials Engineering (3mE), Kris Binon (Flam3D), Guido Verhoeven (Bond voor Materialenkennis/SIM Flanders, Prof. dr. ir. Christian Louter Institut für Baukonstruktion Technische Universität Dresden).

14 Banana fiber pallets

For the export of fruit from the tropics alone, 21 million pallets are needed annually. Many countries in the tropics do not have the right wood themselves to make pallets. That is why wood is imported and then shipped as pallets from the tropics to Europe. It can be done differently: with Yellow Pallets, made from banana fiber.

16 Flexiramics, flexible ceramic fiber material

A new flexible ceramic fiber material, invented by Eurekite, offers a wide range of applications, from batteries and electronics to oil and gas filtration. Eurekite recently raised € 4.2 million in a follow-up investment round, which it intends to use for industrialization of production.

18 TECLA 3D printed earth house

Last January, Italian 3D printer manufacturer WASP completed the 3D printing phase of TECLA, a 3D printed house made of natural materials - mainly earth in this case.

22 RepelWrap

Recently, a Canadian research team from McMaster University won the top prize in the annual 2020 ‘Create the Future’ Design Contest. The Canadian researchers won the prize for a new virus-resistant plastic packaging - RepelWrap - a self-cleaning film that repels viruses and bacteria.

24 Magnetocuring: glue activated by magnetic field

Researchers at NTU Singapore developed a super strong adhesive that does not require a hardener, accelerator, heat or light to cure. They made special nanoparticles, which are added to the epoxy glue, and only cause them to harden when they are exposed to a magnetic field.

26 Liquid window

Scientists at Nanyang Technological University, Singapore (NTU Singapore) have developed a liquid window panel that can simultaneously block and regulate sunlight, as well as retain thermal heat during the day and release it at night. As a result, energy consumption in buildings can be reduced.

28 Sustainable coating from green raw material

Chemists from the University of Groningen, together with colleagues from AkzoNobel (coatings and paint), have developed a new process to convert biomass into a high-quality coating.

32 The lobster way: stronger 3D printed concrete

Researchers of the Australian RMIT university found lobster-inspired printing patterns can make 3D concrete printing (3DCP) stronger and help direct the strength where it’s needed.

34 Blue-light perovskite-based LEDs

Researchers at Linköping University, Sweden, have developed efficient blue light­ emitting diodes based on halide perovskites. The new LEDs may open the way to cheap and energy-efficient illumination.

36 How to give light-capturing ‘solar-cell boosters’ a bright future

To help commercialize so-called luminescent solar concentrators, TU/e researcher Michael Debije along with experts in Italy and the UK propose specific measurement protocols as a new golden standard.

Cover: The production of banana fibre pallets (pag 14) Photo: Yellow Pallet

INNOVATIVE MATERIALS 1 2021

NEWS

Longest wooden bicycle bridge in Europe On February 1, Oldambt, Groningen, has the longest wooden bicycle and pedestrian bridge in Europe; the Pieter Smit bridge. The bridge - a design by architect Nol Molenaar connects Winschoten and Blauwestad. The bridge is 800 meters long and 3.5 meters wide and consists of four combined bridges. It spans partly the Winschoterdiep, the A7, the ecological zone and the Oldambtmeer. The bridge consists mainly of sustainable tropical hardwood with an FSC quality mark. The energy-efficient LED lighting produces minimal light pollution and has no influence on animal life.

The construction consists of sustainable wood from Gabon in Central Africa.

After its completion, the bicycle bridge was the longest in Europe, crossing the 756-meter bicycle bridge in Sölvesborg, Sweden.

The project was commissioned by the Municipality of Oldambt and the Province of Groningen by Strukton Civiel and Oosterhof Holman.

Sustainability was an important item in the construction of the Pieter Smit bridge. For that reason, an almost

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completely wooden construction was chosen. The wood used comes from FSC-managed forests in Africa and is built by the largest timber builder in the Netherlands, Koninklijke Houthandel G. Wijma en Zn. BV. The Pieter Smit Bridge was initially desig-

Photo: Strukton

ned under the name De Blauwe Loper.

In October 2018 it was announced that the bridge was named after Pieter Smit, the mayor of Oldambt who died earlier that year.

Gemeente Oldambt (Dutch)>

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Wij helpen u graag verder met onderzoek en analyse van uw innovatieve materialen.

Bel ons op 026 3845600 of mail info@tcki.nl www.tcki.nl

NEWS

MorphoColour: solar technology with the beauty of butterfly wings Photovoltaic solar installations are by no means always seen as an aesthetic enhancement of a building. An improvement would be to colour the protective glass on solar modules with pigments, but by using pigments the modules would lose a greater portion of their efficiency because the light could no longer penetrate unhindered. The Fraunhofer Institute for Solar Energy Systems ISE developed colored modules, not based on pigments, but on a phenomenon that occurs on the iridescent wings of a certain type of butterfly: Morpho peleides.

These insects, which are native to the tropical rain forest in Central and South America, create the impression of colour thanks to an optical effect rather than pigments. The wings of this butterfly have an extremely fine surface texture that reflects a narrow range of specific wavelengths, which is to say a certain colour. The Fraunhofer ISE scientists apply a similar surface texture and coating to the back of the protective glass on photovoltaic modules using vacuum technology. Depending on the tailoring of the coating, cover glass can be made in say a crisp blue, green, or red. Around 93 percent of light can penetrate this layer, with only around 7 percent being

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reflected to cause the colour effect. The Fraunhofer Research Institute based in Freiburg named its technology MorphoColour after the bright blue morpho butterfly.

According to Fraunhofer, in the future, it will be possible to have photovoltaic and solar thermal modules in the same

colour, mounted almost invisibly next to each other on the roof or on the facade. In that sense, future homes can be aesthetically pleasing plus-energy houses, supplying more energy than they consume.

More at Fraunhofer>

NEWS

Citrus peel plastic might replace PET Plant-based and recyclable plastic bottles now enabled with VTT’s new FDCA technology using citrus peel as raw material.

A new technology developed at VTT Research Centre of Finland Ltd enables the use of pectin-containing agricultural waste, such as citrus peel and sugar beet pulp, as raw material for biobased PEF-plastics for replacing fossil-based PET (polyethylene terephthalate). PET and other polyesters are being widely used in food packaging, plastic bottles and textiles.

According to VTT the carbon footprint of plastic bottles and packaging can be lowered by 50 % when replacing their raw material of PET with PEF polymers, which also provides a better shelf life for food, because PEF would have better barrier properties. Moreover, PEF is a high-quality plastic that can be fully recycled.

The new VTT-technology uses a stable intermediate for the production of FDCA (2,5-furandicarboxylic acid), one of the monomers of PEF, which enables a highly efficient process. In addition, utilising pectin-containing waste streams opens up new possibilities for the circu-

lar economy of plastics.

VTT now wants to upgrade the new technology to an industrial production scale that polymer manufacturers can use immediately. VTT has patented the technology, and the research has been published in the scientific journal Green Chemistry December 2020: ‘A unique

pathway to platform chemicals: aldaric acids as stable intermediates for the synthesis of furandicarboxylic acid esters.’

The article is online> VTT>

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NEWS

Circular M’DAM made entirely of CLT (cross laminated timber) On the Pierebaan in Monnickendam, M’DAM has been under construction since 12 January, and almost entirely constructed out of CLT (cross laminated timber). Never before has a large-scale residential building been built in the Netherlands that is constructed almost entirely of CLT. The flats are almost entirely built in the factory. Because of the use of solid wood, the modular design and the industrial manufacturing process, the building has a net negative CO2 footprint: the sum of the emissions is smaller than the amount of CO2 saved and buffered in the CLT. Moreover, by using wood from sustainably managed production forests, the construction partners are replanting

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more trees than are being used.

Thanks to the industrial manufacturing process, the houses are already being produced while the groundwork is still taking place. This also limits the inconvenience of construction. The façade of the U-shaped building is largely made of wood, partly of traditional brickwork and partly of aluminium façade elements.

The wood construction concept reduces CO2 emissions and is therefore much more sustainable and environmentally friendly than traditional construction projects and provides a healthier living environment. The use of wood and the re-usable construction method mean that the raw materials can be reused in the future.

The plan was developed by BMB Ontwikkeling (part of VolkerWessels). M’DAM was designed by product developer and architect Finch Buildings from Amsterdam. The prefabrication and construction of this unusual timber building concept is being carried out by De Groot Vroomshoop (also part of VolkerWessels). M’DAM will be completed in the summer of 2021.

VolkerWessels>

NEWS

Fungus as a sound absorber Sound absorbers can improve a room’s acoustics. Many of the soundproofing panels used in walls or room fittings in today’s interior designs are made of mineral fibers or synthetic foams.

Some of these materials are not particularly sustainable or easily recycled.

The Fraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT has now teamed up with the Fraunhofer Institute for Building Physics (IBP) to investigate the use of fungus-based materials for the fabrication of eco-friendly sound absorbers.

The original idea came from Julia Krayer, project manager at Fraunhofer UMSICHT in Oberhausen. She has been working on biomaterials for many years. For the current project, Krayer and colleagues are growing hyphae (mushroom mycelium) in the lab. This mycelium is first mixed with a vegetal substrate consisting of straw, wood and waste from food production, and then printed into the desired shape by means of a 3D printer.

The mycelial hyphae spread throughout the substrate and create a solid structure. Once the mycelium has permeated the fine-grained substrate, the product is dried in a kiln in order to kill the fungus. The cell walls of the resulting material are open, meaning that it will absorb sound.

According to Fraunhofer, the potential applications for this mycelial material are not limited to acoustics. The end products could probably be used as insulating material, and even the prospects of using mycelium as a base material for fungal faux leather, fabric and plastic also look promising. In the future, fungus-based materials could be used not only to produce sound absorbers and insulating materials, but also clothing, furniture and housings for electrical appliances. Research is already underway to make this possible.

More at Fraunhofer>

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NEWS

‘Geopolymer concrete will change bridge construction’ The circular bridges ‘Rondje Weerwater’ and ‘Bever’ at the Floriade park in Almere will largely be made of cementless concrete (geopolymer concrete). According to the parties involved, it is the first time in the Netherlands that cementless concrete has been used for the structural parts of the bridge (including the bridge deck). The material is made from residual flows from Almere.

The construction was made by Reimert Bouw en Infrastructuur. According to initiator Bruggencampus, the use of cementless concrete offers a new perspective on the sustainable construction and maintenance of bridges in the future.

Bruggencampus Flevoland-Floriade is an initiative of the province of Flevoland and the municipality of Almere.

This campus is intended as a stimulus for the development and application of innovative and circular bridges. This is important because 40,000 bridges

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and viaducts will have to be replaced in the Netherlands before 2040, of which approximately 2,000 in Flevoland. This requires a completely new approach in terms of material, raw materials, cooperation forms and investment.

The Bruggencampus project started in 2019 and its results will continue and will be visible at Floriade Expo 2022.

In collaboration with the KIWA, the process towards certification was completed in September last year. From that

NEWS

moment on, cement-free concrete could be used in structural parts of the Floriade bridges. A milestone and a good basis but, according to the parties involved, just the beginning. The wider application of cementless concrete (heavily loaded parts) requires more experiments, studies and certifications.

This geopolymer material consists of a concrete mortar where the cement (the binder) has been replaced by an activator with the same binding properties as cement and where primary raw materials (sand and gravel) have largely been replaced by secondary raw materials.

flows into cement-free concrete. Cirwinn BV provides the recycled raw materials; Theo Pouw BV makes cement-free concrete, while the construction is in the hands of Reimert Construction and Infrastructure.

Because this is a completely new product, it is not yet entirely clear what the consequences will be for management and maintenance. Almere is therefore drawing up a monitoring plan together

with KIWA and Reimert, in which the behaviour of the construction is followed in real time. The intention is to build up more knowledge about the material properties of the concrete.

More at Bruggencampus (Dutch)>

By using cementless concrete instead of regular concrete, CO2 emissions are greatly reduced: to more than 50 percent. A number of regional companies are involved in processing the residual

Video

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NEWS

First road with three-layer lignin asphalt Since the end of 2020, the Dutch municipality of Vlissingen has unique metres of asphalt. The construction of this section of the ‘Europaweg Zuid’ consists entirely of lignin-containing asphalt in various layers, some of which are mixed with recycled asphalt. A landmark: never before have all asphalt layers contained lignin.

Wageningen Food & Biobased Research developed the technology that made this possible to replace a large proportion of all bitumen in the road.

The CHAPLIN XL research project at Wageningen University intends to replace bitumen in Dutch asphalt on a large scale by the natural binding agent lignin, in which partners from the asphalt production chain are collaborating. One of the advantages of lignin instead of bitumen in asphalt is that it significantly reduces CO2 emissions and retains the greenhouse gas for a long time. The project is part of a large-scale research programme aimed at making road construction more sustainable. The client for the construction of the road section is North Sea Port. This port authority had the very first test strip of lignincontaining asphalt laid in 2015 based on Wageningen technology, developed in collaboration with AKC. Test strips of lignin asphalt are now spread throug-

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hout the Netherlands. Of all these strips, only the top layer contains lignin, but of the road section now laid by construction company H4A, each layer consists of lignin-containing asphalt, partly mixed with recycled asphalt.

According to Richard Gosselink, lignin expert at Wageningen Food & Biobased Research, it’s technically possible to gradually replace all bitumen in asphalt with biobased components. The next step is for the lignin asphalt to be recognised as a fully-fledged alternative to ‘fossil’ asphalt. If half of the bitumen can be replaced, it is estimated that 20 % of

CO2 emissions can be reduced.

In CHAPLIN-XL, Wageningen Food & Biobased Research contributes years of knowledge about lignin raw materials and the correlation between raw material and quality. In this way, lignin asphalt will be tested in practice in the coming years. The knowledge will also be used in the LCA study together with Utrecht University, the coordinator of CHAPLIN-XL. These LCA results - as well as the financial aspects - are important in order to be able to provide future road builders with sound foundations in tenders. The health and safety conditi-

NEWS ons of the asphalt during production and construction are also mapped out.

In CHAPLIN-XL, Wageningen Food & Biobased Research collaborates with Utrecht University, the Asphalt Knowledge Centre (AKC), Avantium Chemicals B.V., Circular & Biobased Delta, H4A and Roelofs Wegenbouw bv. These parties are also part of the broader CHAPLIN consortium.

WUR>

Video Circular Biobased Delta

NabascoSign: Biobased, circular road sign Every year hundreds of thousands of boards are replaced in the market, so a sustainable alternative can have a major impact. Instead of the conventional aluminum, the NabascoSign road sign consists largely of residual materials.

Pol Heteren and NPSP developed a biobased circular road sign, NabascoSign.

POL Heteren is specialized in everything related to traffic and safety; NPSP makes fiber-reinforced plastics for construction, design, mobility and industry on the basis of biobased and circular raw materials.

The road signs are made from the biocomposite Nabasco. The material is made of reed, lime and resin. Lime (calcium carbonate) is residual material from the water softening process of drinking water companies; reed is a re-

sidual material from nature areas in the Netherlands and bio-resin is produced in France on the basis of residual materials from the biofuel industry. A kind of dough is made from these raw materials, which is pressed into the desired shape under high pressure and temperature.

Due to the use of biobased residual materials, the biocomposite has, according to the manufacturer, a very low CO2 footprint.

There are currently ten different road sign sizes available that are dimensionally suitable for built-up areas and other public places where road signs are required. In the future, the range will be expanded with signs that can also be used outside built-up areas.

More at NabascoSign>

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MAKE IT MATTER

MAKE IT MATTER MAKE IT MATTER is compiled in collaboration with MaterialDistrict (MaterialDistrict.com). In this section new, and/or interesting developments and innovative materials are highlighted.

Guardyl Guardyl is an extremely resistant flexible profile with a natural wood look. This innovative polyurethane is maintenance-free and keeps its original colour over time. The durability of the material makes it the lasting solution for rubrail for yachts, outdoor bridge rails and many other applications. Guardyl is available in wood-look and many colours.

More at MaterialDistrict>

Alucobond Alucobond is a composite panel consisting of two aluminium cover sheets and a fire-retardant or non-combustible mineralfilled core that stands for sustainable construction quality and the highest creative standards. According to the manufacturer, the facade material is distinguished by its flatness, variety of surfaces and colours and excellent conformability. Alucobond is especially suited for ventilated facades and combines energy-efficient construction with architectural quality.

More at MaterialDistrict>

Bamboo X-treme MOSO Bamboo X-treme cladding is a solid, high-density exterior bamboo board, made from compressed bamboo strips.

A special heat treatment process provides Bamboo X-treme with the highest durability class possible in the appropriate EU norms. It also increases the stability and density, and consequently the hardness. Furthermore, contrary to similar wood-based products, this product reaches fire safety class B-s1 d0 (EN 13501-1) without impregnation with expensive and eco-damaging fire retardants.

More at MaterialDistrict>

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MAKE IT MATTER 3D printed steel connectors Large scale metal printing company MX3D teamed up with Japanese architectural construction company Takenaka to create a structural steel connector using robotic 3D metal printing.

MX3D is best known for their 3D printedsteel bridge. The goal of this project is to automate both the design and the production of complex connectors for large structures in the building industry. The Structural Steel Connector is made using Wire Arc Additive Manufacturing (WAAM) and is made of Duplex stainless steel, an alloy with good mechanical properties and corrosion resistance.

More at MaterialDistrict>

Mercury Effect Designer Rado Kirov developed a technique of manipulating a sheet of stainless steel achieving a rippled surface that is mirror polished to dynamically reflect its surroundings. This socalled Mercury Effect technique can be used for wall cladding, artistically covering pillars or fireplaces, flat wall or free-standing sculptures, and furniture.

More at MaterialDistrict>

Ozeon VeroMetal cooperates with Ozeon providing lightweight panels with a real metal surface. The Ozeon panels are developed for applications such as exterior façades. The panels are also suitable for interior wall cladding. Shiny brass, weathered copper, stainless steel, authentic bronze, iron with or without rust, just a few examples of the many different finishes available. The VeroMetal coating is applied to a pressed mineral wool panel.

The result is a high quality panel with the design freedom of compact sheet material combined with a genuine metal appearance.

More at MaterialDistrict>

ND 600 Drainage Material Nophadrain has developed a special ND 600 Drainage System series for trafficable roof surfaces. The separate layers - filter, drainage and protection layer- of the ND Drainage Systems are glued together and are supplied on rolls. The filter geotextile has been specially developed for the application and for stresses during installation e.g. sub-base layers that have to be compacted by using a vibratory plate.

More at MaterialDistrict>

13 | INNOVATIVE MATERIALS 1 2021

INNOVATIVE MATERIALS

Banana pallets can reduce CO2emissions Just for the export of fruit from the tropics, 21 million pallets are needed each year. In the first place, many countries in the tropics themselves do not have the right wood to make pallets. That is why wood is imported and then shipped as pallets from the tropics to Europe. Moreover, thousands of hectares of forest must be cut down for this. It can be different: with Yellow Pallets, made from banana fiber.

The company Yellow Pallet B.V. was first established in January 2012, by entrepreneur Hein van Opstal (MSc, MBA) and Gert Kema (MSc, PhD), scientist at Wageningen University and Research Center (WUR). The idea was simple.

Banana plants grow fast and are abundantly available. On the other hand, conventional pallets are not sustainable and cause CO2 emissions during their life cycle. Why not use the easily available banana fibers to make pallets?

With the support of Startlife, PPM Oost, Wageningen University and Research Center and investment company Both­ SidesNow, Yellow Pallet has been able to conduct research, execute the required tests and to establish the business. Their first factory is stationed in Costa Rica.

The daily management of the company is executed by Hein van Opstal. Gert Kema

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INNOVATIVE MATERIALS provides new job opportunities for the local population and reduces the lifecycle CO2-footprint.

Starting with the costs. The price of sawn wood increases every year leading to higher prices of pallets every year. Over 85 % of the production cost of pallets consist of the required wood. 95 % of all pallets in the world are wooden pallets. Banana fiber is a logical alternative for wood in the tropics where pallets demand is high for export of tropical fruit (e.g. bananas, pineapple and melons) and other products.

According to Yellow Pallet, their factories offer a price to banana growers for their waste banana stems or for the part of the stem not being used for further banana production.

Alternatively, Yellow Pallet has specialized itself in growing a banana variety resistant to diseases that can produce in every 14 weeks a 4 - 6 meter stem. According to Yellow Pallet, the capacity to produce dry fibre of such a plantation will be 4 - 6 times higher than a wooden forest.

Royal HaskoningDHV has executed a study calculating a benefit of 22 % reduced carbon emission compared to wooden pallets, with options to further reduce the emissions. is employed by Wageningen University and Research Center and coordinates global research programs aiming at disease management in banana production.

Yellow Pallet is supported by a group of experienced private impact investors and funds.

Yellow Pallet sells technology to produce transport pallets and blocks made of banana fiber.

These blocks are used in block pallets replacing 26 to 32 % of the wood volume of a block pallet. Factories can offer a more cost-effective pallet.

Using banana fiber has several benefits. It is cost-effective,

Yellow Pallet is growing. The company is scaling up its factory in Costa Rica. It should triple in a year’s time. Yellow Pallet is aiming to sell factories to tropical countries that export a lot of fruit, such as the Philippines, Guatemala, Colombia and Ecuador. According to Van Opstal, the company also receives inquiries from Indonesia, Malaysia, Brazil and China for banana pallet factories. Banana plants also grow there and there is a great need for pallets as well.

Yellow Pallet > Read an interview with Hein van Opstal on the 4TU website>

15 | INNOVATIVE MATERIALS 1 2021

INNOVATIVE MATERIALS

Flexiramics: flexible, ceramic fiber material A new flexible ceramic fiber material, invented by Eurekite, offers a wide range of applications from batteries and electronics to oil and gas filtration. Eurekite is a spin-off from the University of Twente in the field of advanced materials. The company has successfully developed a laboratory scale production process and carried out several projects with international customers. Now Eurekite is ready to scale up production, invest in global market development and expand its patent portfolio. To this end, it raised € 4.2 million in a follow-up investment round and asked technology developer and producer Demcon for the industrialization of production.

Flexiramics is based on the globally recognized expertise of the University of Twente (UT) in materials science and nanomaterials. It is a flexible mat of pure ceramic fibers that is light and flexible like tissue paper, while retaining the key physico-chemical properties of traditional ceramics. Those properties

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of ceramics are heat resistance, electrical insulation and corrosion resistance.

Traditional ceramics, however, are very inflexible, which limits their applications. As a flexible ceramic, Flexiramics offers unique application possibilities in numerous technical fields, including separation membranes in Li-ion batteries,

flexible, heat-resistant printed circuit boards and filtration membranes for the oil and gas industry.

Upscaling

From 2015, Eurekite has focused on the further development of the new cera-

INNOVATIVE MATERIALS

The process of making Flexiramics consists of three main steps. The first one starts with a wet chemical solution. This step is crucial as it defines most of the properties of the final material. The wet chemical solution is shaped into fibers by a spinning process. After that, the liquid is evaporated at a temperature up to 100 °C. The remaining fibers are not yet ceramic. The fibers are then calcined at a temperature between 100 and 400 °C. In the final step a high temperature treatment is applied to the green fibers. During this treatment at circa 1000 °C the fibers are turned into a ceramic material.

According to Eurekite this three-step process allows for flexibility, which opens up a very large range of possibilities.

Different Flexiramics compositions have been produced. The fiber diameter can be tuned between approximately 250 nm and 3000 nm. Both porosity within the fiber as well as porosity between fiber (packing density) can be tuned. The ceramic fibers can be treated to have a polymeric coating or another inorganic coating. Flexiramics can be delivered in different shapes. For instance it can be shaped into a non-woven mat of randomly distributed ceramic fibers. Another variety is the so-called alignedmat: a mat of uniaxially aligned ceramic fibers.

Finally, there is also fibrous powder: wherein the fibers are delivered in the shape of loose powder.

mic material. The aim was to realize a production process on a laboratory scale and carry out projects with international customers to tailor product properties to their specific needs. As a result, small quantities of high-quality material can now be produced and the next step is to produce the larger quantities required for qualification projects with customers.

This step of requires a production line for market development (a pilot production line), explains COO Bas Kerkwijk.

‘Our core competencies lie in materials science and chemistry, not in mechanical engineering, so we started looking for an engineering partner. We chose Demcon because of their track record of industrialization of manufacturing and their experience designing and building high-quality machines and pilot lines.’

Eurekite’s pilot line is scheduled for completion by the end of 2022. Meanwhile, the company will use temporary equipment to produce material to fuel

market development. Additional funding is required for the scale-up of production and commercial activities and for the further development of intellectual property.

Consortium of investors

Between 2015 and 2020, Cottonwood Technology Fund - a Dutch-American venture capital fund - has made start-up and follow-on investments worth € 2.75 million provided to Eurekite. The new follow-up investment round of € 4.2 million includes a substantial loan from RVO (Rijksdienst voor Ondernemend Nederland), the equipment lease facility of the Twente High Tech Fund and a capital injection from a consortium of regional investors, including Lumana Invest, East NL from the Innovation Fund Twente and Demcon.

Eurekite>

Eurekite Eurekite started in 2015 as a spin-off of the UT in the field of advanced materials and is located in Enschede. The company focuses all activities on its core invention, Flexiramics, a flexible ceramic with a unique range of applications in many technical areas. In recent years the concept has proven itself and subsequently a prototype for a platform technology and production process has been successfully developed on a laboratory scale.

Drawing on its expertise in flexible ceramics and Flexiramics in particular, Eurekite currently focuses on application, specific engineering, product delivery and technology development.

17 | INNOVATIVE MATERIALS 1 2021

INNOVATIVE MATERIALS

TECLA 3D printed earth house Last January, Italian 3D printer manufacturer WASP has completed the 3D printing phase in its construction of TECLA, a 3D printed house based on natural materials - mainly soil in this case. It is made with multiple 3D printers operating at the same time. The habitat model was engineered by WASP and designed by Mario Cucinella Architects. It took form as a new circular model of housing entirely created with reusable and recyclable materials, sourced from local soil, carbon-neutral and adaptable to any climate and context.

TECLA (an acronym of Technology and Clay) was made in Massa Lombarda (Ravenna, Italy). In January, the project’s 3D-printing phase is complete with work continuing on the structure’s finishes.

The TECLA adventure started October 2019, when the companies involved began planning the TECLA eco-house, based on research from architecture specialists at the School of Sustainability (SOS) and in cooperation whith the Architectural Association School of Architecture. The School of Sustainability, based in Bologna, is a post graduate practice academy by Mario Cucinella focused on training emerging professionals in the field of sustainability.

Much earlier, in 2012, WASP (World’s

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INNOVATIVE MATERIALS Advanced Saving Project) began developing digital manufacturing processes and 3D printing systems that can be used to manufacture circular homes.

The inspiration for this came from the so-called potter wasp, an insect that builds nests from clay. The company has now developed various printing systems, which usually use locally sourced material such as soil, loam or mud as a printing medium. Nowadays, WASP produces 3D-printed houses in a very short time and in a sustainable way with the first multi-printer Crane WASP system, the company’s flagship for the construction market.

Crane WASP

Crane WASP is a modular collaborative 3D printing system. It is composed of a main printer unit that can be assembled in different configurations depending on the printing area and therefore on the dimensions of the architectural structure to be calculated in 3d. The print area of the single module is 6.60 meters in diameter for a height of 3 meters.

The single module can work self-sufficiently by printing materials of different kinds, like soil, loam, concrete mortar and geopolymers. A single module, can be expanded by adding traverses and printer arms, thus generating an infinite digital manufacturing system.

The system is configured according to project needs and defines the structure of a safe and extremely efficient construction site. Each printer unit has a printing area of 50 square meters and

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INNOVATIVE MATERIALS therefore makes it possible to build independent living modules, of any shape, in a few days.

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350 layers

According to WASP, TECLA is the first eco-habitat built using, at the same time, multiple Crane WASP collaborative printers. The building is a self-supporting habitable structure, that can be fabricated by depositing layers of reusable and recyclable materials such as local soil, on top of one another. In theory,

the resulting habitats are completely carbon-neutral, while being adaptable to any conceivable climate or conditions around the world.

TECLA can be synthesized in 200 hours of printing, 7000 machine codes (G-code), 350 layers of 12 mm, 150 km of

extrusion, 60 cubic meters of natural materials for an average consumption of less than 6 kW. The final installation of TECLA and its presentation are scheduled for spring 2021. www.3dwasp.com>

Voeg informatie toe aan de Kennisbank Biobased Bouwen De Biobased Economy speelt een belangrijke rol in de duurzame ontwikkeling van Nederland en biedt nieuwe kansen voor het bedrijfsleven. Via de kennisbank kunt u kennis vergaren en delen over de beschikbaarheid en toepassingsmogelijkheden van biobased materialen, producten en bouwconcepten. Samen versterken we zo de biobased economie.

Ruim dertig partijen in de bouwsector ondertekenden de green deal biobased bouwen. Deze producenten, architecten, adviseurs en kennisinstellingen delen hun kennis rond kansrijke mogelijkheden van biobased bouwen. Ook de ministeries van Binnenlandse Zaken (Wonen en Rijksdienst), Economische Zaken, en Infrastructuur en Milieu ondersteunen de green deal.

Bouw ook mee aan de biobased economie en voeg uw project- of productbeschrijvingen toe aan deze kennisbank.

Kijk op www.biobasedbouwen.nl voor meer informatie>

advertentie.indd 1

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1-2-2016 15:58:48

RESEARCH

This golden ‘coin’ was made from nanoparticle building blocks, thanks to a new technique developed by Brown University researchers. Making bulk metals this way allows for precise of the metal’s microstructure, which enhances its mechanical properties Credit: Chen Lab/Brown University

Metals might be much harder Metallurgists have all kinds of ways to make a chunk of metal harder. They can bend it, twist it, run it between two rollers or pound it with a hammer.

These methods work by breaking up the metal’s grain structure - the microscopic crystalline domains that form a bulk piece of metal. Smaller grains make for harder metals. A group of Brown University researchers has found a way to customize metallic grain structures from the bottom up. The researchers developed a method for smashing individual metal nanoclusters together to form solid macro-scale hunks of solid metal. Mechanical testing of the metals manufactured using the technique showed that they were up to four times harder than naturally occurring metal structures.

For this study, the researchers made centimeter-scale ‘coins’ using nanoparticles of gold, silver, palladium and other metals. Items of this size could be useful

for making high-performance coating materials, electrodes or thermoelectric generators.

According to the researchers, the key to the process is the chemical treatment given to the nanoparticle building blocks.

Metal nanoparticles are typically covered with organic molecules called ligands, which generally prevent the formation of metal-metal bonds between particles. Chen and his team found a way to strip those ligands away chemically, allowing the clusters to fuse together with just a bit of pressure.

In theory, the technique could be used to make any kind of metal. In fact, the team showed that they could make an exotic form of metal known as a metallic glass. Metallic glasses are amorphous, meaning they lack the regularly repeating crystalline structure of normal metals. That gives rise to remarkable properties. Metallic glasses are more easily moulded than traditional metals,

can be much stronger and more crackresistant, and exhibit superconductivity at low temperatures.

Chen says he’s hopeful that the technique could one day be widely used for commercial products.

Brown University> The article ‘Bulk Grain-Boundary Materials from Nanocrystals’ was published by the journal Chem on January 22. (Yasutaka Nagaoka, Masayuki Suda, Insun Yoon, Na Chen, Hanjun Yang, Yuzi Liu, Brendan A. Anzures, Stephen W. Parman, Zhongwu Wang, Michael Grünwald and Hiroshi M. Yamamoto.) doi.org/10.1016/j.chempr.2020.12.026 The article is online>

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INNOVATIVE MATERIALS

RepelWrap Recently, a Canadian research team from McMaster University won the top prize in the annual 2020 ‘Create the Future’ Design Contest organized by TechBriefs/SAE Media Group.

The Canadian researchers won the prize for a new virus-resistant plastic packaging - RepelWrap - a self-cleaning film that repels viruses and bacteria.

RepelWrap has a self-cleaning surface that can repel all forms of bacteria, preventing the transfer of antibiotic-resistant superbugs and other dangerous bacteria in settings ranging from hospitals to kitchens, and could even reduce the spread of COVID-19. The new plastic surface can be shrink-wrapped onto door handles, railings, and all kind of different surfaces. According to McMaster University, the material is also ideal for food packaging, where it could stop the accidental transfer of bacteria such as E. coli, Salmonella and listeria from raw chicken, meat and other foods, as described in a paper published today by the journal ACS Nano.

The research was led by engineers Leyla Soleymani and Tohid Didar, who collaborated with colleagues from McMaster’s Institute for Infectious Disease Research and the McMaster-based Canadian Centre for Electron Microscopy.

Inspired by the water-repellent lotus leaf, the new surface works through a combination of nano-scale surface engineering and chemistry. The surface is

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textured with microscopic wrinkles that exclude all external molecules. A drop of water or blood, for example, simply bounces away when it lands on the surface. The same is true for bacteria.

The surface is also treated chemically to further enhance its repellent properties, resulting in a barrier that is flexible, durable and inexpensive to reproduce.

The researchers tested the material

McMaster University-onderzoekers (en winnaars van de ontwerpwedstrijd ‘Create the Future’) Leyla Soleymani en Tohid Didar

RESEARCH using two of the most troubling forms of antibiotic-resistant bacteria: MRSA and Pseudomonas, with the collaboration of Brown and his colleagues at McMaster’s Institute for Infectious Disease Research.

The research was published by ACS Nano in 2019 titled ‘Flexible Hierarchical Wraps Repel Drug-Resistant Gram-Negative and Positive Bacteria’ by Leyla Soleymani and Tohid Didar, McMaster University. Their co-authors on the paper include Sara M. Imani, Roderick Maclachlan, Kenneth Rachwalski, Yuting Chan, Bryan Lee, Mark McInnes, Kathryn Grandfield and Eric D. Brown. (doi.org/10.1021/acsnano.9b06287) More at McMaster University> The Design contest at TechBriefs>

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RESEARCH

Magnetocuring: glue activated by magnetic field Researchers at NTU Singapore developed a super strong adhesive that does not require a hardener, accelerator, heat or light to cure. They made special nanoparticles, which are added to the epoxy glue, and only cause them to harden when they are exposed to a magnetic field. This costs much less energy than, for example, heating (as is often the case) and in many cases is also more convenient in terms of production technology.

Scientists from Nanyang Technological University, Singapore (NTU Singapore), have developed a new way to cure adhesives using a magnetic field. Conventional adhesives like epoxy which are used to bond plastic, ceramics and wood are typically designed to cure using moisture, heat or light. They often require specific curing temperatures, ranging from room temperature up to 80 degrees Celsius.

The curing process is necessary to

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crosslink and bond the glue with the two secured surfaces as the glue crystallises and hardens to achieve its final strength.

NTU’s new ‘magnetocuring’ glue can cure by passing it through a magnetic field. This is very useful in certain environmental conditions where current adhesives do not work well. Also, when the adhesive is sandwiched between insulating material like rubber or wood, traditional activators like heat, light and air cannot easily reach the adhesive.

The new magnetocuring adhesive is made by combining a typical commercially available epoxy adhesive with specially tailored magnetic nanoparticles made by the NTU scientists. It does not need to be mixed with any hardener or accelerator, unlike two-component adhesives (which has two liquids that must be mixed before use), making it easy to manufacture and apply.

It bonds the materials when it is activated by passing through a magnetic field,

RESEARCH

Gluing with heat treatment often takes place with industrial ovens that use a lot of energy

which is easily generated by a small electromagnetic device. This uses less energy than a large conventional oven.

According to the NTU-scientists these magnetocuring adhesives offer potential application in a wide range of fields, including high-end sports equipment, automotive products, electronics, energy, aerospace and medical manufacturing processes. Laboratory tests have shown that the new adhesive has a strength up to 7 megapascals, on par with many of the epoxy adhesives on the market.

How it works

The new adhesive is made of two main components - a commercially available epoxy that is cured through heat, and nanoparticles made from a chemical combination including manganese, zinc and iron (MnxZn(1-x)Fe2O4). These nanoparticles are designed to heat up when electromagnetic energy is passed through them, activating the curing process. The maximum temperature and rate of heating can be controlled by these special nanoparticles, eliminating overheating and hotspot formation.

Without the need for large industrial

ovens, the activation of the glue has a smaller footprint in space and energy consumption terms. The energy efficiency in the curing process is crucial for green manufacturing, where products are made at lower temperatures, and use less energy for heating and cooling.

For instance, manufacturers of sports shoes often have difficulty heating up the adhesives in between the rubber soles and the upper half of the shoe, as rubber is a heat insulator and resists heat transmission to the conventional epoxy glue. An oven is needed to heat up the shoe over a long time before the heat can reach the glue.

Using magnetic-field activated glue bypasses this difficulty, by directly activating the curing process only in the glue.

Moving forward, the team hopes to engage adhesive manufacturers to collaborate on commercialising their technology. They have filed a patent through NTUitive, the university’s innovation and enterprise company. They have already received interest in their research from sporting goods manufacturers.

Developed by Professor Raju V. Ramanujan, Associate Professor Terry Steele and Dr Richa Chaudhary from the NTU School of Materials Science and Engineering, the findings were published in the scientific journal Applied Materials Today. The article ‘Magnetocuring of temperature failsafe epoxy adhesives’ was published in Dec issue of Applied Materials Today. doi.org/10.1016/j. apmt.2020.100824.

It’s online>

video

More at NTU>

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RESEARCH

‘Liquid window’ Scientists at the Nanyang Technological University, Singapore (NTU Singapore) have developed a liquid window panel that can simultaneously block the sun to regulate solar transmission, while trapping thermal heat that can be released through the day and night, helping to reduce energy consumption in buildings. Earlier this year the results were published in the scientific journal Joule.

Windows are a key component in a building’s design, but they are also the least energy-efficient part.

Conventional energy-saving low-emissivity windows are made with expensive coatings that cut down infrared light passing into or out of a building, thus helping to reduce demand for heating and cooling. However, they do not regulate visible light, which is a major component of sunlight that causes buildings to heat up. To develop a window to overcome these limitations, the NTU researchers turned to water, which absorbs a high amount of heat before it begins to get hot - a phenomenon known as high specific heat capacity. They created a mixture of micro-hydrogel, water and a stabiliser and filled a double window

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RESEARCH with it. Thanks to the hydrogel, the liquid mixture turns opaque when exposed to heat, thus blocking sunlight, and, when cool, returns to its original ‘clear’ state.

The team found through experiments and simulations that this system can effectively reduce energy consumption in a variety of climates, due to its ability to respond to a change in temperature.

At the same time, the high heat capacity of water allows a large amount of thermal energy to be stored instead of getting transferred through the glass and into the building during the hot daytime.

The heat will then be gradually cooled and released at night. As a result of these features, the NTU research team believes that their innovation is best suited for use in office buildings.

They found that this ‘liquid window’ can reduce up to 45 per cent of heating, ventilation, and air-conditioning energy consumption in buildings in simulations, compared to traditional glass windows.

It is also 30 per cent more energy efficient than commercially available low-emissivity (energy-efficient) glass, while being cheaper to make.

The research team is now looking to

A composite photo showing the window in the before (cool) and after (hot) state

collaborate with industry partners to commercialise the smart window.

The paper titled ‘Liquid Thermo-Responsive Smart Window Derived from Hydrogel’, was published in Joule, November 2020 NTU>

Video

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RESEARCH

Future coatings from nature Organic chemists from the University of Groningen and AkzoNobel (paints and coatings) developed a process that allows them to turn biomass into a high-quality coating using light, oxygen and UV light. This process combines a renewable source with green chemistry and could replace petrochemical-based monomers such as acrylates, which are currently used as building blocks for coatings, resins and paints. A paper on the new process was published in the journal Science Advances, last December.

Coatings are everywhere. They protect surfaces from scratches, influences of the weather or everyday wear. Most coatings are made up of polymers based on acrylate monomers, with the global production of acrylate exceeding 3.5 million tonnes a year, all produced from fossil oil.

with scientists from coating producer AkzoNobel. The starting point was lingocellulose. Lignocellulose makes up 20 to 30 per cent of the woody parts of plants and is the most abundantly available raw biomass material on Earth. Currently, it is mainly used as a solid fuel or used to produce biofuels.

To make these coatings more sustainable, scientists from the University of Groningen, led by Professor of Organic Chemistry Ben Feringa, teamed up

According to George Hermens, a PhD student in the Feringa group and first author of the paper in Science Advances,

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No waste

lignocellulose biomass van be cracked using acid to produce furfural. But this needs to be modified to make it suitable for the production of coatings.

He used a process that has been developed in their group to convert the furfural into a compound, hydroxybutenolide, that resembles acrylic acid. The chemical conversion uses only light, oxygen and a simple catalyst and produces no waste.

The only side product is methyl formate, which is useful as a replacement for

RESEARCH chlorofluorocarbons (cfc’s) in other processes.

Less reactive

Part of the structure of hydroxybutenolide is similar to acrylate, but the reactive part of the molecule is a ring structure.

This means that it is less reactive than acrylate. The challenge was to further modify the molecule so that it would produce a useful polymer. This was achieved by adding different green or biobased alcohols to the hydroxybutenolide, creating four different alkoxybutenolide monomers.

Coatings

These monomers can be transformed into polymers and coatings with the help of an initiator and UV light.

Coatings are made up of cross-linked polymer chains. By combining different monomers, the researchers could get cross-linked polymers with different properties. For example, while all polymers would coat glass, one combination was able to also form a coating on plastic. And by adding more rigid monomers, a harder coating was formed, with properties comparable to those of coatings on cars. In this way, these coatings are adaptable for different purposes.

Patent

The research team managed to create coatings from a renewable source, lignocellulose, using green chemistry, with

Lignocellulose biomass is cracked using acid to produce furfural. Using visible light and oxygen, furfural is converted into hydroxybutenolide, which is then modified using different alcohols to produce alkoxybutenolide monomers, that can be polymerized into coatings using UV light (Photo: George Hermens and Paco Visser, University of Groningen)

the quality of coatings similar to that of current acrylate-based coatings. For two steps in the process, patent applications have been filed with AkzoNobel, the industrial partner in the project.

Text: RUG> The article ‘A coating from nature’ is online>

Partners The project was initiated by the Advanced Research Center Chemical Building Blocks Consortium (ARC CBBC), a Dutch national public-private research centre that develops new chemical processes and chemical building blocks for novel energy carriers, materials and chemicals for sustainable chemistry. The ARC CBBC is a national initiative with partners from industry, academia and government.

There are three universities involved (Utrecht University, the University of Groningen and Eindhoven University of Technology) and major industrial partners (AkzoNobel, Shell, Nouryon and BASF), as well as the ministries of Education, Culture and Science and of Economic Affairs and Climate Policy and the Dutch Research Council (NWO).

Hermens is now working on a different building block derived from furfural to produce other types of polymer coatings.

Researchers George Hermens and second author Thomas Freese (left)

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RESEARCH

Self assembling molecules make nanofibers that are stronger than steel MIT researchers have designed small molecules that spontaneously form nanoribbons when water is added. These molecules include a Kevlar-inspired ‘aramid’ domain in their design, in green, which fixes each molecule in place and leads to nanoribbons that are stronger than steel. Parts of the molecules attracted to or repulsed from water, shown in purple and blue respectively, orient and guide the molecules to form a nanostructure. This image depicts three Kevlar-inspired ‘aramid amphiphile’ nanoribbons

Self-assembly is ubiquitous in the natural world, serving as a route to form organized structures in every living organism. This phenomenon can be seen, for instance, when two strands of DNA - without any external prodding or guidance - join to form a double helix, or when large numbers of molecules combine to create membranes or other vital cellular structures.

For the past couple of decades, scientists and engineers have been following nature’s lead, designing molecules that assemble themselves in water, with the goal of making nanostructures, primarily for biomedical applications such as drug delivery or tissue engineering. But these small-molecule-based materials tend to degrade rather quickly and they’re chemically unstable, too. The whole structure falls apart when you remove the water, particularly when any kind of external force is applied.

A team of MIT scientists, lead by Julia Ortony, assistant professor in MIT’s Department of Materials Science and Engineering (DMSE), have designed a new class of small molecules that spontaneously assemble into nanoribbons with

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unprecedented strength, retaining their structure outside of water.

The material the MIT group constructed - or rather, allowed to construct itself - is modelled after a cell membrane. Its outer part is hydrophilic, whereas its inner part is hydrophobic. This configuration provides a driving force for self-assembly, as the molecules orient themselves to minimize interactions between the hydrophobic regions and water, consequently taking on a nanoscale shape.

The shape, in this case, is conferred by water, and ordinarily the whole structure would collapse when dried. But the researchers came up with a plan to keep that from happening. When molecules

are loosely bound together, they move around quickly, analogous to a fluid; as the strength of intermolecular forces increases, motion slows and molecules assume a solid-like state. The idea, is to slow down molecular motion through small modifications to the individual molecules, clinging the molecules to each other, for instance by a dense network of strong hydrogen bonds.

The MIT team incorporated that capability into their design of a molecule that has three main components: an outer portion that likes to interact with water, aramids in the middle for binding, and an inner part that has a strong aversion to water. The researchers tested dozens of molecules meeting these criteria before finding the design that led to long

RESEARCH ribbons with nanometer-scale thickness.

Then they measured the nanoribbons’ strength and stiffness to understand the impact of including Kevlar-like interactions between molecules. They discovered that the nanoribbons were unexpectedly sturdy - stronger than steel, in fact.

MIT> ‘Self-assembly of aramid amphiphiles into ultra-stable nanoribbons and aligned nanoribbon threads’ (Ty Christoff-Tempesta, Yukio Cho, Dae-Yoon Kim, Michela Geri, Guillaume Lamour, Andrew J. Lew, Xiaobing Zuo, William R. Lindemann & Julia H. Ortony) was published on January 21 in Nature Nanotechnology.

Professor Julia Ortony (left) and PhD student Yukio Cho. Ortony and her team have designed a new class of small molecules that spontaneously assemble into nanoribbons with unprecedented strength, retaining their structure outside of water (Photo: Lee Hopkins)

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RESEARCH

The lobster way: stronger 3D printed concrete Researchers of the Australian RMIT university found lobster-inspired printing patterns can make 3D concrete printing (3DCP) stronger and help direct the strength where it’s needed.

And combining the patterns with a concrete mix enhanced with steel fibers can deliver a material that’s stronger than traditionally-made concrete. The study (Influences of Printing Pattern on Mechanical Performance of Three-Dimensional-Printed Fiber-Reinforced Concrete) was published in 3D Printing and Additive Manufacturing on 30 December 2020.

Digital manufacturing technologies like 3D concrete printing (3DCP) have immense potential to save time, effort and material in construction. They also promise to push the boundaries of architectural innovation, yet technical challenges remain in making 3D printed concrete strong enough for use in more free-form structures.

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The most conventional pattern used in 3D printing is unidirectional, where layers are laid down on top of each other in parallel lines. The new study published in a special issue of 3D Printing and Additive Manufacturing investigated the effect of different printing patterns on the strength of steel fibre-enhanced concrete.

Previous research by the RMIT team found that including 1-2 % steel fibres in the concrete mix reduces defects and porosity, increasing strength. The fibres also help the concrete harden early without deformation, enabling higher structures to be built.

The team tested the impact of printing the concrete in helicoidal patterns

RESEARCH most promising for the construction of complex 3D-printed concrete structures, according to the researchers.

Further studies will be supported through a new large-scale, 5 × 5 m mobile concrete 3D printer recently acquired by RMIT - making it the first research institution in the southern hemisphere to commission a machine of this kind.

The robotic printer will be used by the team to research the 3D printing of houses, buildings and large structural components.

RIMT> The article ‘Influences of Printing Pattern on Mechanical Performance of Three-Dimensional-Printed Fiber-Reinforced Concrete’ is online>

(inspired by the internal structure of lobster shells), cross-ply and quasi-­ isotropic patterns (similar to those used for laminated composite structures and layer-by-layer deposited composites)

and standard unidirectional patterns.

The results showed strength improvement from each of the patterns, compared with unidirectional printing. However, the spiral patterns appear to be the

Video

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RESEARCH

Blue-light perovskite-based LEDs Researchers at Linköping University, Sweden, have developed efficient blue light-emitting diodes based on halide perovskites. The new LEDs may open the way to cheap and energyefficient illumination.

LEDs manufactured from halide per­ovskites could be a cheaper and more eco-friendly alternative for both illumination and LED-based monitors.

Perovskites are a family of semiconducting materials defined by their cubic crystal structure. Halide perovskites have at least one element from the halogen group. They have good light-emitting properties and are easy to manufacture.

Using elements from the halogen group, i.e. fluorine, chlorine, bromine and iodine, perovskites can be given properties that depend on the chemical composition of the crystal.

LEDs for green and red light have already been created with perovskites, but one

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RESEARCH Germany, China and Denmark, has managed to create halide perovskites that give stable emission in the wavelength range 451-490 nanometres - corresponding to deep blue to sky blue colours.

Colour shift

colour, blue, has so far been lacking, making it impossible to achieve white light.

According to Feng Gao, professor at the Department of Physics, Chemistry and

Biology at Linköping University, blue light is the key to bringing light-emitting perovskites to practical applications.

Feng’s research group, in collaboration with colleagues in Lund, Great Britain,

Metal-halide perovskites are easily colour-tuneable over the whole visible spectrum by simple alloying. Unfortunately, they exhibit demixing and a blue LED turns green during operation. The team now has found a method that can prevent this colour shift by controlling the film crystallisation dynamics when creating the perovskite. These findings pave the way for stable perovskite alloys.

The challenge of creating blue light in perovskites is that it requires a chemical composition with a large fraction of chloride, which makes the perovskite unstable. However, stable perovskites with the desired amount of chloride can be created with the aid of the ‘vapour assisted crystallisation technique’.

Furthermore, the Linköping University researchers have achieved an energy efficiency of up to 11 % for the blue perovskite-based LEDs.

Future

According to Feng Gao, this work is still about basic research, and applications are still some way off in future.

Perovskite LEDs are a young technology and have some way to go before they see the light of day. Currently, the short lifetime and poor performance of blue LEDs are the main obstacles for perovskite light­emitting diodes before they can start to compete with existing technologies such as light-emitting diodes based on organic and inorganic semiconductors. The team will keep working on that to make PeLEDs comparable to the other technologies, says Feng Gao. The article ‘Mixed Halide Perovskites for Spectrally Stable and High-Efficiency Blue Light-Emitting Diodes’ was published in Nature Communications, January 2021. DOI: 10.1038/s41467020-20582-6.

It’s online>

Weidong Xu, postdoc at the Department of Physics, Chemistry and Biology at Linköping University is part of the research group that has managed to create halide perovskites that give stable emission in the wavelength range 451-490 nanometres (Thor Balkhed)

University of Linköping>

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RESEARCH

Test with LSC-based SONOBs, (SOlar NOise Barriers) at ‘s Hertogenbosch Photo: Heijmans (Innovative Materials, Volume 3 2015)

How to give light-capturing ‘solar-cell boosters’ a bright future To help commercialize so-called luminescent solar concentrators, TU/e researcher Michael Debije along with experts in Italy and the UK propose specific measurement protocols as a new golden standard.

Solar panels convert light to electricity but have limited efficiency, although this can be improved with bright, colourful, light-trapping slabs of luminescent materials called luminescent solar concentrators (LSCs). Unlike solar panels, LSCs can be favorably integrated into urban

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settings to create a sustainable, visually appealing environment. Despite being around since the late 1970s, LSCs have struggled to have the same commercial impact as solar panels. According to TU/e researcher Michael Debije this is partially due to a lack of measurement

standards. With collaborators from the UK and Italy, he has devised a set of LSC measurements whose adoption could ease commercialization of LSCs. Although solar PV panels are almost omnipresent in society and contribute to the energy transition, there are draw-

RESEARCH

backs. The dark colour of solar panels is not pleasing to the eye. They also exhibit reduced performance in shaded areas

and under cloudy conditions, are only available in limited shapes and sizes, and can only collect light from one side. And

solar PV panels only respond to certain wavelengths of light.

LSC’s

Another light-based technology can address some of the aesthetic and operational limitations by complementing solar PV panels, thus allowing solar PV panels to be used in almost any location.

Luminescent solar concentrators (LSCs) consist of luminescent materials - luminophores - coated on the surface of a polymer or glass plate. Light is captured by the luminophores at one wavelength, and then re-emitted at a longer wavelength.

Michael Debije standing next to part of the Solar Noise Barrier project, which stood in Den Bosch

Unlike PV panels, LSCs are sensitive to diffuse light, visually pleasing, and are not limited to use on rooftops. Critically, LSCs can increase the sensitivity of PV panels to more wavelengths of light.

Semiconductor-based solar PV panels are limited by their sensitivity to certain wavelengths of light. When photons with sufficient energy hit the semiconductor materials, they generate electrons.

However, if the photons have too much energy, any electrons generated have too much energy to be properly har­­ves­ ted. That’s where LSCs come to the rescue. High-energy photons are captured by luminophores, transported through the material via total internal reflection, and then re-emitted at longer wavelengths. PV cells beside the edges of the LSC then absorb the longer wavelength light. LSCs can’t compete straight up with solar panels on electricity output. But they can provide solar panels with more useable light.

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RESEARCH Identity

According to Debije, LSCs lack proper identity, and that’s not good for the technology. While their functionality is impressive, there is a critical issue with LSCs. The fact that LSCs improve the efficiency of PVs has led to a problem with standards. Currently, it’s difficult to compare the performance of different LSC devices alone because many researchers evaluate LSCs in the context of PV-technologies.

An additional problem is that some researchers view LSCs as photonic devices.

The lack of consensus has been damaging to their widescale use, an issue that deeply concerns Debije. Progress has been slowed by the lack of standard reporting methods for LSCs, meaning it has been impossible to compare data collected for the past 40 years. This is problematic, Debije noted.

Impact

Motivated by the lack of proper protocols to classify LSC technologies, Debije, along with Rachel Evans (University of Cambridge, UK) and Gianmarco Griffini (Politecnico di Milano, Italy), have devised a series of measurements that can be carried out by any laboratory.

These measurement approaches are presented in a recent paper in the journal Energy & Environmental Science.

A good example of a company that deals with LSC technology is Lusoco, a technical start-up based in Eindhoven.

Lusoco produces glass that harvests energy during the day and emits light at night.

The company thus focuses on the market for signage and built environments.

The key to the technology is the use of fluorescent dyes that absorb sunlight and light and channel it to the edge of the panel. Lusoco uses fluorescent ink for this, printed on glass or intermediate layers. The result is a highly visible

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The aim is to make things easy for the LSC community to compare different LSC designs. Prior to this, standardized measurement approaches were unavailable. In addition to presenting measurement approaches for LSC, Debije and his collaborators propose that moving forward LSCs must be treated as photonic devices.

According to the TU/e-researcher, this technology could have a huge impact on urban design, energy production, chemical processing, and hydrogen production. There are an increasing number of labs working on LSCs, but there is also an increasing number of detractors who highlight the absence of standardization.

Luminescent solar concentrators can

print that harvests light during the day and guides it to the edges. Solar cell strips have been applied to the side edges of the printed glass panel, which make it possible to harvest energy.

For this purpose, flexible thin film solar cells are used that are integrated into the frame of the construction and store the solar energy in an integrated battery.

In addition to harvesting energy, the same coating is also used to emit light at night, simply by inverting the principle with lighting applied to the edges.

move beyond complementing solar PV panels, they must. The protocols devised

by Debije, Evans, and Griffini can tilt the balance in favor of rapid and standardized deployment. Nevertheless, LSCs must step out of the shadow of solar PV panels.

Text: TU Eindhoven> ‘Laboratory protocols for measuring and reporting the performance of luminescent solar concentrators’ was published last January by Energy & Environmental Science.

The article is online>

The principle can be used as signage applications or decoration.

Losoco.com>

Video: an LSC information board developed by Lusoco that harvests solar energy during the day and uses it again at night

ENTERPRISE EUROPE NETWORK

Enterprise Europe Network (EEN) supports companies with international ambitions The Enterprise Europe Network (EEN) is an initiative of the European Commission that supports entrepreneurs in seeking partners to innovate and do business abroad. The Network is active in more than 60 countries worldwide.

It brings together 3,000 experts from more than 600 member organisations – all renowned for their excellence in business support.

Database

Every company can participate by adjusting its profile to the database. This company will be brought to the attention in the country in which it wants to become active. At the same time it is possible to search for partners.

EEN advisers actively assist in compiling the profile, which is drawn up in a certain format. The EEN websites also contain foreign companies that are looking for Dutch companies and organizations for commercial or technological cooperation. The EEN advisers support the search for a cooperation partner by actively deploying contacts within the network. In addition, Company Missions

and Match Making Events are regularly organized. All these services are free of charge.

There are five types of profiles:

• Business Offer:

the company offers a product

Video: How Enterprise Europe Network works

• Business Request:

the company is looking for a product

• Technology Offer:

the company offers a technology

• Technology Request:

the company is looking for a technology

• Research & Development Request:

the organization seeks cooperation for research

When a company has both a Business Offer and a Business Request (or another combination), two (or even more if applicable) profiles are created.

The profile includes the most essential

information about the nature of the supply or demand, the ‘type of partner’ that is intended and the expected cooperation structure.

Get in touch with your local network contact point by selecting the country and city closest to where your business is based. They can help you with advice, support and opportunities for international partnerships.

For sustainable building and the creative industry, contact ir. drs. Hans Kamphuis: T: +31 (0) 88 042 1124 M: 06 25 70 82 76 E: hans.kamphuis@rvo.nl For Materials contact Nils Haarmans: T: +31 (0) 88 062 5843 M: 06 21 83 94 57 More information websites can be found at the Europe Network websites: www.enterpriseeuropenetwork.nl http://een.ec.europa.eu

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ENTERPRISE EUROPE NETWORK The Enterprise Europe Network Materials Database: Request for partnership: March 2021.

Intrested? contact hans.kamphuis@rvo.nl>

100% biobased resin and composites and new uses for mixed plastic streams

A UK company has launched a plant based resin that competes with synthetic resins on price. A variety of household and industrial products have been produced with various composites. Interestingly, the resin binds mixed petrochemical plastics and promises completely new circular economy products. Developers and manufacturers of plant fibre products or boards, and handlers of mixed plastics are sought for technical cooperation, licensing and manufacturing agreements

Development of ultra-high performance concretes (UHPC) with local materials and optimization of the obtained products

A Spanish SME offers their expertise in UHPC and special concretes to develop (ultra) high performance concretes with local materials, improving their ratio performance/cost, to replace steel or normal concrete. They optimize structural design to reduce weight or increase durability and impact strength and assess the life cycle of the product. They seek partners from civil engineering, aquaculture, industry and energy sectors for a services agreement, research or technical cooperation.

Environmentally friendly foaming technology for refillable packaging and industrial applications

A UK company has prototyped a new foaming technology based on environmentally friendly gases such as air or nitrogen which are used to produce very consistent microfoams. Industrial manufacturers or users of foams are sought to jointly develop appliances, devices and processes, incl. refillable aerosol dispensers, fire suppression systems, systems to dispense environmentally friendly insulating material under technical cooperation agreements and license agreements.

23 March 2021 | Future of Building 2021 | Virtual - Home (b2match.io) Wirtschaftskammer Österreich, Wiedner Haupstraße 63 | 1045 Wien Advantage Austria from EEN-host organization WKÖ together with the Enterprise Europe Network Austria organize an exclusive congress and b2b matchmaking platform for Austrian and international companies as well as for decision makers operating in the construction sector. Join us and learn about the latest technologies and materials, share new project ideas, and find international cooperation partners for new business opportunities.

After the Future of Building Brokerage Event, you are warmly welcome to participate in the Vienna Congress on Sustainable Building BauZ! that takes place from 24-25 March 2021. Please note that a separate registration is necessary for BauZ!

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EVENTS The corona crisis makes it uncertain whether events will actually take place on the scheduled date. Many events are postponed or online. The Agenda below shows the state of affairs as of March 2021.

For recent updates: www.innovatievematerialen.nl JEC World 2021 9 - 11 March 2021, Paris

ICC8 2021 25 - 30 April 2021, Busan

EuroBLECH 2021 9 - 12 March 2021, Hannover

Partec 2021 26 - 28 April 2021, Nürnburg

Additive Manufacturing Forum 2021 11 - 12 March 2021, Berlin

23th Wear Of Materials conference 26 - 28 April 2021, Online

Solids 2021 17 - 18 March 2021, Dortmund

Ceramic Expo 2020 USA 3 - 5 May 2021, Cleveland

Future of Building 2021

Rapid.Tech + FabCon 3.D 4 - 6 May 2021, Erfurt

23 March 2021, online

9th Conference on CO2-based Fuels and Chemicals 23 - 24 March 2021, Cologne

VETECO 2021 4 - 7 May 2021, Feria de Madrid

Metav reloaded 2021 23 - 26 March 2021, Düsseldorf

TechTextil 2021 4 - 7 May 2021, Frankfurt am Main

Hannover Messe 12 - 16 April 2021, Hannover

International Conference on Natural Fibers (ICNF) 17 - 19 May 2021, Funchal

Steinexpo 2021 14 - 17 April 2021, Homberg

Fastener Fair Stuttgart 2021 18 - 20 May 2021, Stuttgart

Nordbygg 2021 20 - 23 April 2021, Stockholm

1st Renewable Materials Conference, Hybrid 18 - 20 May 2021, Cologne

Nederlandse Metaaldagen 21 - 23 April 2021, Den Bosch

Maintenance Dortmund 2021 19 - 20 May 2021, Dortmund

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Innovative Materials is an interactive, digital magazine about new and/or innovatively applied materials.

Innovative Materials provides information on material innovations, or innovative use of materials. The idea is that the ever increasing demands lead to a constant search for better and safer products as well as material and energy savings. Enabling these innovations is crucial, not only to be competitive but also to meet the challenges of enhancing and protecting the environment, like durability, C2C and carbon footprint.

By opting for smart, sustainable and innovative materials constructors, engineers and designers obtain more opportunities to distinguish themselves.

As a platform Innovative Materials wants to help to achieve this by connecting supply and demand.

Innovative Materials is distributed among its own subscribers/network, but also through the networks of the partners. In 2021 this includes organisations like M2i, MaterialDesign, 4TU (a cooperation between the four Technical Universities in the Netherlands), the Bond voor Materialenkennis (material sciences), SIM Flanders, FLAM3D, RVO and Material District.