IM20235EN by Innovatieve Materialen

Volume 5 2023

NEW MODEL TO HELP VALORIZE LIGNIN FOR BIO-BASED APPLICATIONS LITHIUM ON A STRING PLASMA AGAINST PFAS HOW TO MAKE COLOR-CHANGING ‘TRANSFORMERS’ WITH POLYMERS NANOSCALE 3D PRINTING OF METALS

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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 2023 (6 editions) costs € 44,25 (excl. VAT) Members of KIVI and students: € 25,- (excl. VAT)

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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 (TU Delft)

24 New model to help valorize lignin for bio-based applications

32 Lithium on a string

30 Plasma against PFAS

32 How to make color-changing ‘Transformers’ with polymers

Shape and color changing are key survival traits for many animals. Chameleons can change their body to hide from predators, to reflect their moods, or even to defend their territory, while some soft-bodied animal-like octopuses, squids, and cuttlefish can change both their color and shape to signal or camouflage. Mimicking these capabilities using artificial polymer materials holds great potential in sensing, soft robotics, and the fashion and art industries. During her research, PhD candidate Pei Zhang has realized some incredible colour changing and shape morphing abilities in polymer materials. Pei Zhang defended her PhD thesis at the department of Chemical Engineering and Chemistry on August 31st.

34 Nanoscale 3D printing of metals

Late last year, Caltech University researchers revealed that they had developed a new fabrication technique for printing microsized metal parts containing features about as thick as three or four sheets of paper. The team recently presented the technique that allows objects to be printed a thousand times smaller: 150 nanometers, comparable to the size of a flu virus. The work was conducted in the lab of Julia R. Greer, Ruben F. and Donna Mettler Professor of Materials Science, Mechanics and Medical Engineering; and Fletcher Jones Foundation Director of the Kavli Nanoscience Institute. It is described in a paper appearing in the journal Nano Letters.

Cover: Recycling of refractory materials avoids 800,000 tons of CO₂ (Fraunhofer ILT, page 16)

INNOVATIVE MATERIALS 5 2023

NEWS

3D printing with coffee Coffee is one of the most popular drinks worldwide, but it also creates waste. Scientists estimate that an average of fifteen million tons of coffee grounds are released annually, most of which ends up in landfills or is burned. And that's a shame, because coffee grounds contain a whole range of interesting substances, such as sugars (about half by weight), proteins and lignins. It also contains potassium, nitrogen, magnesium and phosphorus. For that reason, and because of the scale of the waste problem, attempts have been made over the past decade to give it a useful purpose. Even though coffee grounds have now found various useful applications, including as a soil improver, the vast majority still ends up in the landfill or incinerator. Scientists from the ATLAS Institute and Department of Computer Science at the Colorado University of Boulder (CU Boulder) have now developed a method for 3D printing a wide range of objects using a paste made entirely out of old coffee grounds, water and a few other sustainable ingredients. The team has already experimented with using coffee grounds to craft jewelry, pots for plants and even espresso cups. The technique is also simple enough that it will work, with some modifications, on most low-cost, consumer-grade 3D printers. The group presented its findings this summer at the Association for Computing Machinery’s Designing Interactive Systems conference in Pittsburgh. According to project leader and assistant professor Michael Rivera, the method is quite simple. Dried coffee grounds

A 3D printer lays down used coffee grounds to make a pot for plants (Credit: Michael Rivera)

are blended with two other powders: cellulose gum and xanthan gum, both common compostable food additives. The blend is then mixed with water to form a kind of slurry, with which objects can be printed after the necessary adjustments to the 3D printer. Once dried, the 3D printed coffee grounds material is as strong as unreinforced concrete, according to the scientists. Most consumer 3D printers print with some type of thermoplastic material, the most common of which is polylactic acid (PLA). This is a biobased plastic and theoretically compostable, but it is not widely accepted by composting companies and generally ends up in landfill. The new filament aims to reduce the amount

of PLA required and is biodegradable. After drying, the objects become as hard as unreinforced concrete. More at Boulder>

Video

Once you're finished with 3D printed coffee objects, you can toss them into a grinder and reuse the material to print again (Credit: Michael Rivera)

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NEWS

Transparent wood-based coating doesn’t fog up

Lignin nanoparticles form colourful coatings when they are applied as multilayer films (Photo: Alexander Henn/Aalto Universiteit)

Researchers of the Aalto-university (Helsinki, Finland) have developed a way to turn a waste material from wood into a biobased transparent film that can be used for anti-fogging or anti-reflective coatings on glasses or vehicle windows. According to Aalto, such coatings are not only an alternative to current synthetic materials, but are also valuable as CO2 storage. Lignin is an abundant waste product in paper and pulp production that is very

difficult to process, so it’s usually burned to produce heat. Scientists would prefer to use lignin for a more high-quality application. Creating lignin nanoparticles to use for anti-fogging coatings isn’t a new idea, but according to Aalto, scientists haven’t yet been able to turn them into transparent films. The team used acetylated lignin and developed an improved way to esterify it in a reaction that takes just a few minutes

and happens at the relatively low temperature of 60 °C. It resulted in surprising properties. For instance, the material turned out to be ideal for making photonic films with anti-condensation and anti-reflection properties. In addition to anti-fogging and anti-reflective coatings, the new approach can also make coloured films from lignin nanoparticles. By controlling the thickness of the coating and using multi-layer films, the team created materials with different structural colours. According to the team, the ease of the reaction and its high yield mean that it could profitably be scaled up to industrial levels. Lignin-based products could be commercially valuable and simultaneously act as carbon sinks, helping relieve the current fossil fuel-dependence and reduce carbon dioxide emissions. According to the Aalto scientists, high value-added applications like this are important to drive lignin valorisation and move us away from using lignin only as a fuel. The study carried out as part of FinnCERES, the Academy of Finland’s flag ship centre for materials bioeconomy research. It was published in Chemical Engineering Journal under the title ‘Transparent lignin nanoparticles for superhydrophilic antifogging coatings and photonic films’ It’s online> More at Aalto University>

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RESEARCH

Making hydrogen from waste plastic could pay for itself Hydrogen is viewed as a promising alternative to fossil fuel, but the methods used to make it either generate too much carbon dioxide or are too expensive. Rice University researchers have found a way to harvest hydrogen from plastic waste using a low-emissions method that could more than pay for itself. That is interesting because current hydrogen gas production processes have environmental disadvantages or are simply very expensive. More than 90 million tons H2 are consumed annually worldwide. More than 95% of this 'grey' hydrogen is synthesized via steam reforming of methane obtained from fossil fuels, mainly natural gas or coal. This process produces eleven tons of CO2 per ton of H2. There is also 'Green H2', which is made by the electrolysis of water and using sustainably generated electricity. This produces no CO2, but costs two to three times more, making it currently economically unrealistic.

James Tour (left) and Kevin Wyss (Photo: Gustavo Raskosky/Rice University)

A study from Rice University now shows that hydrogen is an important byproduct of a process previously developed to

Scanning electron microscope (SEM) image of layered stacks of nano-scale flash graphene sheets formed from waste plastic (Image: Kevin Wyss/Tour lab)

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produce graphene. The method - Flash Joule heating - is a process introduced in 2020 by Rice University's Tour lab to

Transmission electron microscope (TEM) image of layered stacks of nano-scale flash graphene sheets formed from waste plastic (Image: Kevin Wyss/Tour lab)

NEWS/RESEARCH make graphene from plastic waste. The starting material is a mixture of ground (waste) plastic and a carbon additive (for conductivity). This mixture is placed between electrodes in a tube and exposed to intense heat (up to 3100 °K) in a few seconds. As a result, all elements - including hydrogen - evaporate except carbon, which remains in the form of graphene. When Flash Joule heating was developed, scientists saw that many volatile gases were being produced, but they did not know what, for the simple reason that they did not have the instruments to study their exact composition. With

funding from the United States Army Corps of Engineers, the Tour lab has since acquired the necessary equipment to characterize the evaporated contents. This not only provided information about the composition of the gas, which turned out to contain hydrogen, but also enabled the researchers to recover the hydrogen. For instance, polyethylene consists of 86 percent carbon and 14 percent hydrogen. The Rice team has now shown that they can recover 68 percent of that atomic hydrogen as a gas with a purity of 94 percent.

tic would more than pay for itself. If the graphene produced were sold for only 5 percent of the normal market value, hydrogen production would even be free. The research was published in September in Advanced Materials under the title 'Synthesis of Clean Hydrogen Gas from Waste Plastic at Zero Net Cost.' (https://doi.org/10.1002/ adma.202306763) More at Rice>

According to the scientists involved, the production of hydrogen from waste plas-

Sustainable recovery of phosphate from wastewater Selective removal of phosphate residues from wastewater can be done in a more sustainable process, providing greater opportunities for reuse, all thanks to magnetic adsorption and desorption. At least, that is what Wageningen University & Research, together with various partners, is trying to demonstrate in the MAD project: ‘Recovery and Valorization of Phosphorus Compositions from Wastewater Streams Using Magnetic Adsorption-Desorption (MAD)’. Currently, phosphate is mainly removed through chemical precipitation or biological processes in which phosphate accumulating bacteria are involved. These processes are effective, but the removed phosphate is rarely reused in, for example, the production of fertilizer products. Reuse becomes challenging with precipitation methods, in which iron and aluminum salts are added, as phosphate is bound into the sludge

requiring various techniques for its release. In biological processes phosphorus ends up inside the bacteria cells in the sewage sludge. The direct application of this sludge on agricultural fields is increasingly restricted due to e.g. the presence of persistent organic pollutants and heavy metals. This is a pity because phosphate is valuable and scarce. In the MAD-process, magnetite particles play a crucial role in the removal of phosphate from wastewater. After adsorption, the phosphate-containing particles are separated from water using a magnetic field. The use of magnetic separation is not exclusive to the MAD process: other processes, such as ViviMag, also rely on this method to recover phosphorous. However, in the research conducted at Wageningen Food & Biobased Research, phosphate can be recovered directly

from water (instead of forming phosphate sludge) without creating additional waste flows and without the addition of chemicals, such as iron salts. According to the WUR scientists the method is not only very energy-efficient and selective (only phosphate attaches to the magnetic substance), but also reversible: the phosphate and magnetite can be separated. This makes the valuable phosphate available again, isolated and in its original form, to the market. We can use this principle to remove phosphate in both aerobic and anaerobic conditions, without adding salts. The research was published last September in PNAS under the title 'Colorful low-emissivity paints for space heating and cooling energy savings'. (https://doi. org/10.1073/pnas.2300856120) Much more at Wageningen University & Research>

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RESEARCH

Making PLA-bioplastics that are easier to compost Scientists of the Michigan State University’s (MSU) School of Packaging have developed a way to make a promising, sustainable alternative to petroleum-based plastics more biodegradable.

At the moment, less than 10 percent of plastic waste is recycled in the U.S. That means the bulk of plastic waste ends up as trash or litter, creating economic, environmental and even health concerns.

The team behind a new compostable bio-based plastic, from left to right, postdoctoral researcher Anibal Bher, doctoral students Wanwarang Limsukon and Pooja Mayekar, and Rafael Auras, Amcor Endowed Chair in Packaging Sustainability (Photo: Matt Davenport/MSU)

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Another bonus is that plastics destined for the compost bin wouldn’t need to be cleaned of food contaminants, which is a major obstacle for efficient plastic recycling. Recycling facilities routinely must choose between spending time, water and energy to clean dirty plastic waste or simply throwing it out. The team worked with what’s known as polylactic acid, or PLA, which seems like an obvious choice in many ways. It’s been used in packaging for over a decade, and it’s derived from plant sugars rather than petroleum. Plus, researchers know that PLA can biodegrade in industrial composters. These composters create conditions, such as higher temperatures, that are more conducive to breaking down bioplastics than home composters. Although poly lactic acid is a sustainable, biobased and industrially compostable polymer, it has a difficult abiotic degradation process, limiting its organic recovery to well-managed industrial composting facilities. And even there, composting PLA sometimes proves problematic, making industrial composters shy away from accepting bioplastics like PLA.The breakdown of PLA in a home composting bin was even considered impossible by many. A good part of the problems lies in the

NEWS/RESEARCH PLA can sit around for 20 days before microbes start digesting it in industrial composting conditions. To get rid of that lag time and enable the possibility of home composting, the MSU-team integrated a carbohydrate-derived thermoplastic starch into PLA. The presence of 30 percent starch was found to significantly improve the microbial activity of the PLA composite. In addition, starch accelerates the biodegradation of pure PLA by acting as a food reservoir for the growth of microorganisms during chemical and enzymatic hydrolysis. Conclusion: Starch can be used to improve the degradation of PLA in industrial composting conditions by reducing the lag phase of PLA disintegration and, even under mild conditions such as those in home composting, by inducing biodegradation during the first days. Close-up of the bioreactors (Photo: Matt Davenport/MSU)

Conditioned chamber in Rafael Auras’ lab at MSU (Photo: Matt Davenport/MSU)

slow start of the bacterial degradation process. Before microorganisms can attack PLA, it must first be broken down to a point where they can use it as food.

Although industrial compost settings can get PLA to that point, that doesn’t mean they do it quickly or entirely. In its experiments the team showed that

The research was published earlier this year in ACS Sustainable Chemistry & Engineering under the title 'Breaking It Down: How Thermoplastic Starch Enhances Poly(lactic acid) Biodegradation in Compost─A Comparative Analysis of Reactive Blends'. It's online> More at MSU>

'No energy transition without raw material transition' From cobalt and lithium for producing batteries, to iridium for producing hydrogen. The success of the energy transition is determined to a great extent by the availability of scarce raw materials from a small number of countries. To reduce that dependence, a materials transition is needed in addition to an energy transition. Dutch research institute TNO analyzed four examples that show how the organization is working on alternative raw materials and production processes for

even better batteries, hydrogen electrolysers, solar panels and wind turbines. Knowledge institutes such as TNO work together with technology companies on innovative battery materials. A good example is the Battery Competence Center, set up to reduce material dependence and build a knowledge lead in sustainable battery technology in the Netherlands. Another initiative - COBRA (Cobalt-free Batteries for FutuRe Automotive Applications - is aimed at developing a new

generation of cobalt-free lithium-ion batteries. Alternatively, the common metals nickel, iron and aluminum are used. According to TNO, a lot of profit can be achieved, especially in the battery. For example, LionVolt, a TNO spin-off at Holst Center, is working on so-called '3D solid-state' batteries. This technology brings the next generation of batteries to the market, which are intrinsically safe, lightweight, charge very quickly and have a much longer lifespan. Read the entire article at TNO>

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RESEARCH

New insulating paint: less energy consumption, costs and CO2-emissions Stanford University scientists have invented a new kind of paint that can keep homes and other buildings cooler in the summer and warmer in the winter, significantly reducing energy use, costs, and greenhouse gas emissions. Space heating and cooling accounts for about 13 percent of global energy use and about 11 percent of greenhouse gas emissions. The new paints reduced (under laboratory conditions) the energy for heating by approximately 36 percent and cooling by almost 21 percent. In simulations of a typical mid-rise apartment building in different climate zones across the United States with the new paint on exterior walls and roofs, total heating, ventilation, and air conditioning energy use declined 7.4 percent over the course of a year. The newly invented paints have two layers applied separately: an infrared reflective bottom layer using aluminum flakes and an ultrathin, infrared transparent upper layer using inorganic nanoparticles that comes in a wide range of colors. The infrared spectrum of sunlight causes 49 percent of natural heating of the planet when it is absorbed by surfaces. For keeping heat out, the paint can be applied to exterior walls and roofs. Most of this infrared light passes through the color layer of the new paints, reflects off the lower layer, and passes back out as light, not being absorbed by the building materials as heat. To keep heat inside, the paints are applied to interior walls where, again, the lower layer reflects the infrared waves that transfer energy across space and are invisible to the human eye. Specifically, up to about 80 percent of high mid-infrared light is reflected by the paints, doing most of the work of

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Objects made of different materials in different shapes, covered with the new paint (Photo: Yucan Peng)

keeping heat inside during cold weather and outside during hot weather. The color layer also reflects some near-infrared light, enhancing the reduction in air conditioning. The research team tested their paints in white, blue, red, yellow, green, orange, purple, and dark gray. They were 10 times better than conventional paints in the same colors at reflecting high mid-infrared light, the researchers found. The paints can be applied beyond

buildings to improve energy efficiencies elsewhere. For example, they could cover trucks and train cars used for refrigerated transportation, in which cooling costs can take up to half the transportation budget. More at Stanford University>

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NEWS

Wood modification boosts biomass conversion By adding a naturally occurring polymer that makes wood more porous, scientists have engineered trees easier to disassemble into simpler building blocks. Fossil fuels are the major source of energy, chemicals and many materials but are responsible for a substantial portion of greenhouse gas emissions. To reach carbon neutrality, much of what’s made from fossil fuels today will have to be made from biomass tomorrow. With growing demand for sustainable materials and renewable energy, plant-based feedstocks have been investigated, but converting woody plant biomass to fuel and other useful products is chemically and energetically very demanding. Until now, research into converting woody biomass into simpler components has mainly focused on the complex polymers already present in wood.

Callose is produced in response to wounding of the plant tissue. Even though callose is not a constitutional component of the plant's cell wall, it is related to the plant's defense mechanism. It can be deposited as a thick plug on the transverse walls of the sieve vessels. The deposition may be temporary and is the cause or consequence of reduced transport through these elements of the vascular bundle or the bark.

Surprisingly, callose does not interact with other polymers, but acts as a kind of cell wall spacer that attracts water. The researchers expect that the modified wood can significantly improve the production of biomaterials and biofuels. They also hope that our finding by introducing a new polymer into wood will inspire other researchers to introduce other types of polymers for customized applications.

The Cambrigde researchers successfully infiltrated callose into the secondary cell walls of poplars. This callose-enriched wood was found to exhibit interesting new properties, such as increased hygroscopicity and porosity, making the polymers more accessible for extraction and conversion into simpler building blocks such as sugars or bioethanol.

The results of the research were published last September in Nature Plants under the title 'Ectopic callose deposition into woody biomass modulates the nano-architecture of macrofibrils'. It's online> More at Cambridge>

Model of poplar macrofibril assembly without (left) and with callose deposition (right). Callose self-aggregates in between macrofibrils, which explains the observed increase in secondary cell wall porosity. The range of pore size affected is 4 - 30 nm, which is in the size range of hydrolytic enzymes. As such, callose is believed to act as a hydrophilic spacer of secondary cell wall polymer, further promoting access to hydrolytic enzymes for subsequent saccharification (Figure originall published in Bourdon et al, 2023 Nature Plants

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NEWS

Grand for research into the possibilities of iron powder as energy carrier Iron powder can store energy in a very compact, cheap, safe, environmentally friendly and CO2-free manner. This combination makes it a promising solution for greening energy-intensive industry and, for example, coal and power plants. Science financier NWO and organisations involved are therefore making 900.000 euros available for research into the potential of iron powder as an energy carrier on an industrial scale. The research - taking place under the name CIRCL, Closing the Iron Reduction-Combustion Loop - involves Metalot, RIFT, Shell and EIRES. The project team consists of Niels Deen, professor of multiphase and reactive flows at the Department of Mechanical Engineering, Giulia Finotello (assistant professor at Mechanical Engineering), Ivo Roghair (assistant professor at Chemical Engineering & Chemistry) and Martin van Sint Annaland (professor at Chemical Engineering & Chemistry). The research focuses specifically on the regeneration of burned iron powder, also called iron oxide. How does that work? Burning iron powder releases energy in the form of heat. Heat that you can use, for example, to heat houses in a green way - and on an industrial scale. The residual product released during combustion is iron oxide. This can be recaptured and converted into iron powder with hydrogen from green electricity, for reuse. This creates a sustainable cycle, with iron as a green energy carrier. Deen and his colleagues focus on the

An example of a fluidized bed reactor, but on a small scale (Photo: Bart van Overbeeke)

step from iron oxide back to iron powder. His team collaborates with TU/e spin-off RIFT, which has built a production plant in Arnhem that includes a so-called fluidized bed furnace into which iron oxide is poured.

projects through the Open Technology Program in September 2023. The total amount involved is 5.8 million euros. In addition, companies and other organizations involved are investing approximately 950 thousand euros in the projects.

The NWO Applied and Technical Sciences domain awarded funding to a total of seven application-oriented research

Original text TU/e>

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NEWS

New biobased asphalt binder: less toxic, more sustainable

The ASU Parking and Transit Services team prepares the final layer of an AirDuo asphalt before it is compacted. The test will take place in the parking lot of the Gammage Auditorium (Photo: Bobbi Ramirez/ASU)

Asphalt is primarily known for use in roadways, but it's also used to pave playgrounds, bicycle paths, running tracks and tennis and basketball courts. Outdoor use on driveways, roofs and parking lots, especially in direct sunlight, may result in exposure to toxic fumes. A team from Arizona State University, led by Associate Professor Ellie Fini in the School of Sustainable Engineering and the Built Environment (SSEBE), has developed AirDuo, a new, patent-pending asphalt binder that not only diminishes toxic fumes of the overall asphalt-surfaced area, but also increases sustainability. But perhaps most importantly it reduces

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health hazards for those exposed to asphalt-surfaced areas, especially for those performing the installation. AirDuo's first local trial was initiated in late August as a patch in ASU's Gammage Auditorium parking lot. Asphalt binder is the glue that holds together the stones, sand, gravel and other aggregates in asphalt pavements. The AirDuo binding mixture is composed of low-carbon, bio-based materials that are an alternative to more toxic petroleum products, also known as bitumen. Moreover, AirDuo acts as a toxicity filter for the overall product. After the traditional blend of aggregates and binder is laid on the roadways,

the stress from heat, sun, weather and traffic causes the release of breakdown products - molecules that vaporize some of which are odorous, highly toxic or both. Fini has now conducted several studies into alternative asphalt binders, including an investigation into how iron-rich biochar absorbs volatile organic compounds from asphalt surfaces and how it is both an environmentally friendly and cost-effective alternative to bitumen components. (Iron-Rich Biochar to Adsorb Volatile Organic Compounds Emitted from Asphalt-Surfaced Areas, ACS Sustainable Chemistry & Engineering, February 2023).

NEWS She then investigated different types of biochar, derived from six different types of woody biomass and one type of algae, and polyethylene terephthalate granules as a carrier to introduce biochar into bitumen. This led to the publication earlier this year in ACS Advanced Sustainable Systems (Bio-Carbon as a Means of Carbon Management in Roads), which describes Air Duo Paving (AP1) in detail Fini's laboratory studies showed an emissions reduction of almost 70 percent when using AirDuo. Although it is not a one-to-one translation to the field, according to Fini, it clearly illustrates the reduction of toxic fumes. The mixture also emitted significantly less odour than conventional bitumen mixtures. The raw material for AirDuo is therefore biomass that has already removed CO2 from the air before harvesting. Accord-

Ellie Fini Photo: Bobbi Ramirez/ASU)

ing to Fini, AP1 thus helps to achieve a sustainable built environment and at the same time ensures fewer health risks for both asphalt workers and those who use asphalt surfaces.Follow-up research fo-

cuses on setting up larger-scale practical tests and investigating the possibility of using algae grown in wastewater. More at ASU>

New products from kelp The use of kelp - seaweed - is interesting for a variety of sectors, including food, animal feed, such as degradable plastics and agriculture. The Norwegian GP Seaweed is therefore investigating options to expand kelp cultivation in Norway to production on an industrial scale, and to develop new, sustainable and climate-positive kelp products. GP Seaweed is a so-called Green Platform project led by the Norwegian research institution SINTEF Ocean and has twelve partners representing both research and industry. The project should pave the way for Norway to become an international leader in kelp and seaweed cultivation. Both Saccharina latissima (sugar kelp) and Alaria esculenta (winged kelp) will be used in the study, as both species have different properties and the planned products will utilize the entire biomass, without creating residual waste. According to SINTEF, large-scale production of biomass and the use of underutilized species such as kelp are essential to replace various traditional plastic applications, such as packaging. More at bij SINTEF>

Winged kelp has many exciting use cases which will be examined in the GP Seaweed project (Photo: SINTEF)

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RESEARCH

Stretchable electronics: novel liquid metal circuits for flexible, self-healing wearables There is growing interest in soft, stretch able sensors that can be incorporated into textiles and collect information from the person wearing that same textile. Such wearables can, for instance help to recover from joint injuries or monitor the heart rhythm of heart patients. It's not that far yet. Disruptive innovations in wearable technology are often limited by the electronic circuits - which are usually made of conductive metals that are either stiff or prone to damage that power these smart devices. Researchers from the National University of Singapore (NUS) have recently invented a new super flexible, self-healing and highly conductive material suitable for stretchable electronic circuitry. This breakthrough could significantly improve the performance of wearable technologies, soft robotics, smart devices and more.

The new conductive and stretchable ‘super-material’ developed by NUS researchers can heal cracks or cuts almost instantaneously to maintain its electrical conductivity (Photo: NUS)

The newly engineered material, called the Bilayer Liquid-Solid Conductor (BiLiSC), can stretch up to a remarkable 22 times its original length without sustai-

Liquid metal circuitry using a newly engineered material called Bilayer Liquid-Solid Conductor (BiLiSC) allows devices such as wearables to withstand large deformation and even self-heal to ensure electronic and functional integrity (Photo: NUS)

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ning a significant drop in its electrical conductivity. This electrical-mechano property, which has not been achieved before, enhances the comfort and effectiveness of the human-device interface, and opens up a wide array of opportunities for its use in healthcare wearables and other applications. According to the researchers involved, BiLiSC is an ideal technology for use in wearable devices, considering the shape and varied movements of the body. The material consists of two layers. The first layer is a self-assembled pure liquid metal, which can provide high conductivity even under high strain, reducing the energy loss during power transmission and signal loss during signal transmission. The second layer is a composite material containing liquid metal microparticles and it is able to repair itself after breakage. When a crack or crack occurs, the liquid metal from the microparticles flows into the crack, allowing the material to repair itself almost immediately and maintain its original conductivity.

RESEARCH The NUS team demonstrated that BiLiSC can be made into various electrical components of wearable electronics, such as pressure sensors, interconnections, wearable heaters, and wearable antennas for wireless communication. In laboratory experiments, a robotic arm using BiLiSC interconnections was quicker in detecting and responding to minute changes in pressure. In addition, the bending and twisting motion of the robotic arm did not impede the transmission of signals from the sensor to the signal processing unit, compared to another interconnection made with a non-BiLiSC material. The NUS team is now working on material innovation and process fabrication. They are looking to engineer an improved version of BiLiS that could be printed directly without needing a template. This would reduce cost and improve the precision in fabricating the BiLiSC. More at NUS>

Prof Lim Chwee Teck (left), Dr Chen Shuwen (right) and their team have developed a novel liquid-metal material (held by the researchers) suitable for making flexible and unbreakable circuitry for stretchable electronics (Photo: NUS)

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RESEARCH

Recycling of refractory materials avoids 800,000 tons of CO₂

Used refractories are detected with laser measurements and reused in a CO₂-saving way (Photo: Fraunhofer ILT, Aken)

Within the European research project ReSoURCE, experts from nine different companies and institutes work together to develop sustainable solutions for the recycling of refractory materials. Refractory materials can withstand high temperatures above 1,500 °C. They are indispensable for industrial furnaces that produce, for example, glass or ceramics, non-ferrous metals and steel. The life of refractory products varies from a few days to many years - depending on the materials, the temperature in the melting vessel and other operating parameters. As a result, approximately 32 million tons of used refractory materials are produced worldwide each year, of

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which only a fraction is recycled. The production of refractories from primary raw materials produces significant amounts of CO2, mainly because carbon dioxide must be removed from carbonate-like raw materials. In addition, a large part of the raw materials are imported to Europe. This also includes critical raw materials with high-risk supply chains. This alone is an importand reason to reprocess used refractory materials and bring them into a circular economy, as there are currently no significant alternatives.

Automatic sorting system

Refractory products are often precisely adapted to customer requirements. The

optimal composition of the high-temperature-resistant materials depends on the intended application, the production processes and the associated chemical properties of the process media. Before they can be recycled, they must therefore be separated as accurately as possible. For that reason the project focuses on an automatic sorting system for used refractory materials. Using a laser unit, the components of the material used on a conveyor belt are identified without coming into contact with them. The laser technology is provided by the company Laser Analytical Systems & Automation GmbH (LSA) from Aachen, a spin-off of the Fraunhofer Institute for Laser Technology ILT.

RESEARCH over distances of up to one meter in fractions of a second. Within the joint project, the company InnoLas Laser GmbH from Krailling in Germany is developing the laser beam source, which emits special pulse groups to quickly penetrate unrepresentative surface layers on the refractory bricks used. Only then is it possible to analyze the underlying material.

Visible scattered light from the 532 nm laser output of a laser in the laboratory of InnoLas Laser GmbH in Krailling (InnoLas Laser GmbH)

Fraunhofer ILT is active in developing new applications for laser spectroscopy, including sorting into pure materials for recycling with laser-induced breakdown spectroscopy (LIBS). The institute has now developed an inline measuring technique that performs a direct analysis of metal scrap on a conveyor belt and detects the composition of each piece of scrap. This multi-ele-

ment analysis can detect a large number of alloys and those experiences are now being transferred to refractory materials.

Artificial intelligence

LSA specializes in the development and production of real-time laser analysis systems for industrial applications. The systems use pulsed laser radiation to obtain contactless chemical information

The laser source for the ReSoURCE project is being developed specifically for LIBS. LSA integrates optical measurement technology with material handling to develop a system suitable for industrial use. Fraunhofer ILT evaluates the data from the LIBS system. In this case they measure spectra containing the chemical information combined with further optical sensor data and analyzed using artificial intelligence. In this way, the system determines the exact composition of the refractory products and sorts the individually used refractory bricks into different material classes. The research partners expect they can increase the industry's potential recycling share from the previous 7 to 30 percent up to 90 percent as a result of the project findings. The idea is to combine the latest analysis technology with state-of-the-art software to solve a current societal problem by reducing reduce European CO2 emissions by up to 800,000 tons per year. www.ilt.fraunhofer.de/en

Project ReSoURCE The ReSoURCE project goal is the development of a working sensor-based system for refractory waste sorting and powder handling. If the project is successful, it will enable the robust engineering of an automated sorting equipment that will increase the recycling of refractory breakout material from the current estimate of 7 - 30 percent worldwide (plus 10 percent of downcycling) to a total 90 percent. With approximately 32 million tons of used refractories generated annually, the ecological and societal benefits will be considerable. The project is funded by the European Health and Digital Executive Agency (HaDEA) in the Horizon Europe Framework program (HORIZON). The total budget is 8.5 million euros. Six million euros are funded by the EU, one million by the UK. The project’s duration is from June 2022 to November 2025 (42 months). The consortium consists of nine members (four academia and five industry). Partners come from Austria, England, Germany, Ireland and Norway. The project is led by RHI Magnesita. Other partners involved in the project are LSA GmbH (GER), Fraunhofer institute (GER), SINTEF (NOR), Montanuniversität Leoben (AT), Innolas Laser GmbH (GER), NEO (NOR), CPI (UK), and Crowdhelix (IRE).

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RESEARCH

Sustainable building with loam Environmentally friendly, widely available and recyclable: loam is a clean alternative building material. Moreover, the CO2 footprint of loam is much less than that of concrete, for instance, making it more interesting for the construction sector. Dr. Ellina Bernard from Empa's concrete and asphalt laboratory in Dübendorf, chair of Sustainable Construction at ETH Zurich, is studying the possibilities of loam as a sustainable building material. The research project is funded by the Swiss National Science Foundation (SNSF) with an Ambizione grant. According to Empa, the potential of loam is enormous, for instance as an alternative to concrete. Although it cannot replace concrete for all construction purposes, it can be an excellent alternative to concrete in a wide range of non-load-bearing structures; even in load-bearing walls of homes. Consider pressed loam in the form of prefabricated building blocks. According to Empa, such air-dried bricks have a more favorable energy balance than their baked counterparts, bricks. However, according to Ellina, loam is not yet a true miracle product. Although the material has been used for around 10,000 years, making it one of the more primitive building materials in human history, the use of loam as a sustainable alternative has still not really taken off. This is partly because the geological composition of the natural material varies worldwide, which makes standardized production and use difficult. On the other hand, conventional cement is currently often added to the loam to create a stable building material, but this addition obviously worsens the ecological footprint of the material. The Empa researchers want to gather more knowledge about the material, define standards for its composition and associated mechanical strength, and on this basis develop a clean, alternative building material for industrial use.

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The geological composition of clay varies around the world. Ellina Bernard wants to develop standards for use in the construction industry (Image: Empa)

Unlike cement, which derives its stability from chemical bonds, the minerals in loam form physical bonds as they dry. Stability such as concrete cannot be achieved in this way. That is why Empa is now looking for stabilizing binders and a promising candidate currently appears to be magnesium oxide. According to Empa, if magnesium oxide is produced in a sustainable way, it has an excellent ecological footprint compared to calcium-containing cement. In addition, magnesium oxide shortens the drying time and prevents the unwanted formation of lumps in the loam through the formation of nanocrystals. In initial laboratory experiments with magnesium oxide loam, the team has now achieved a compressive strength

of 15 megapascals - according to the researchers - many times more compared to untreated loam. Loam with added cement scores up to 20 megapascals, and a wall subject to a fairly limited load, such as in an apartment, should be able to withstand up to 10 megapascals. According to Ellina Bernard, this is just the beginning. Since she wants to assess the sustainability of building materials holistically, the laboratory experiments must also be accompanied by life cycle analyses that record the durability, deconstruction and recycling of the materials. And that is exactly what Empa will be doing in the near future. Meer bij Empa>

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RESEARCH

Corrugated plastic unveils a new design principle for programmable materials Corrugated plastic turns out to be exemplary of a new class of ‘multistable’ metamaterials that can reversibly change shape. This insight can lead to new applications, from robots to medical devices. Physicists Anne Meeussen (previously Leiden University/AMOLF, now Harvard University) and Martin van Hecke (Leiden University/AMOLF) describe these materials in a Nature publication.

From a flower unfurling its petals to a robot grabbing an object: things are changing shape all around us. Over the years, researchers have been inspired by nature to create materials that can shift from one shape to another. But there is one problem. Usually, these shapes are not stable, and if they are stable they cannot be reshaped. Clay has a similar issue; a shape created with soft clay is

The metamaterial changes from a sheet to a stable 3-dimensional form and back

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not stable, but once the clay has been baked, its shape cannot be reset. In their Nature publication, Meeussen and Van Hecke describe a new governing for the design of true ‘multistable’ metamaterials. For the first time, they succeeded to make materials that can take on multiple stable conditions, which can also easily be reversed.

RESEARCH Rolls, spirals

The basis of the discovery is a material with a deceptively simple structure: sheets of plastic - or any other flexible material - that contain corrugations, or grooves. When this groovy sheet is pulled, the grooves buckle and form an extended ridge perpendicular to the grooves. This ridge will stay in place even if you stop pulling - and force the sheet into a new shape. Combining various ridges results in beautiful rolls, spirals and helical shapes, which are stable even when standing independently. However, when the sheet is even further pulled apart, the ridges disappear, and reshaping can start again. Meeussen discovered that every buckled

groove functions as a defect, and that neighboring defects ‘feel’ each other: if you bring them closer, they repel each other. But, if two defects are exactly next to each other, they stick together. This means that the ridges exist of chains of defects that attract and lock each other in. The newly discovered principles of multistability and shapeshifting materials open many different types of applications, such as foldable emergency housing; medical devices such as stents, that can enter the body in one shape and once inside fold open into another stable, useful shape; and even robot parts that can easily switch back and forth bet-

ween programable shapes are feasible. This research is published last September in Nature under the title 'Multistable sheets with rewritable patterns for switchable shape-morphing'. University of Leiden>

Video

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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.

Bio Block Architectural firm Skidmore, Owings & Merrill (SOM), in collaboration with Prometheus Materials, developed Bio Block: a type of concrete blocks, made using naturally occurring microscopic algae. This is used to make a material that is comparable to calcium carbonate as generated in coral reefs. When mixed with an aggregate, it forms a building material with comparable or better physical and thermal properties to standard Portland cement-based concrete, but without a carbon footprint. More at MaterialDistrict>

Nature inclusive facade of biocomposite Dutch biocomposite company NPSP, in collaboration with Studio Marco Vermeulen, developed a biobased, natureinclusive facade, with contains integrated nesting boxes for birds and insects. The facade of the Innovatie Paviljoen Marineterrein Amsterdam is made of NPSP’s Nabasco 8012, a composite made from local, natural residual flows of reed, lime from drinking water companies and partly biobased resin. The ingredients are mixed and pressed into a mold, creating a strong material that is suitable for facades. More at MaterialDistrict>

Sustainable structures made of 3D printed wood Mexico-based company MANUFACTURA and furniture and design workshop La Metropolitana created 3D printed objects made of wood. The project, called The Wood Project or Un Proyecto de Madera, aims to reduce the amount of sawdust created in woodworking projects. La Metropolitana generates daily over 200 kilograms of sawdust. In the project, this sawdust is repurposed to make 3D printed structures More at MaterialDistrict>

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MAKE IT MATTER Coating that cools the streets Roofing company GAF developed StreetBond, a coating for pavement, that comes in various colours and reflects sunlight, cooling the streets. Within cities, the heat island effect is a major problem. StreetBond pavement coatings bond to both asphalt and concrete surfaces to provide a durable, aesthetic finish that helps protect and extend the life of pavement.

More at MaterialDistrict>

Biodegradable concrete formwork of sawdust Researchers at the University of Michigan (US) created a biodegradable formwork made of sawdust to mitigate wood waste in the process of laying concrete. Wood is often used as formwork for concrete construction, but after a single use is discarded. In addition, in the United States alone, 1.5 million kilograms of sawdust is dumped in landfills, and even more is burned. More at MaterialDistrict>

A ‘living facade’ made of aluminium panels The National Biodiversity Pavilion in Mexico City, designed by architect Fernanda Ahumada and Studio FR-EE, features a facade of moving aluminium panels that respond to light and wind. The dynamic facade is composed of thousands of movable 30 × 20 cm aluminum modules that sway with the wind. (Photo: Mariola Soberon/César Belio)

More at MaterialDistrict>

Sheet material from olive waster The Greek design studio Koukos de Lab opposite Koukoutsi made a sheet material from olive waste. The material can be used as floor coverings, tiles, but also to make furniture. The studio has now designed a coffee table, a sofa and a stool with the material. It is also available in limited form for other uses.

(Photo: Koukos de Lab)

More at MaterialDistrict>

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INNOVATIVE MATERIALS

New model to help valorize lignin for bio-based applications

(Photography: TU/e)

Woody biomass and wheat straw are all sources of the natural polymer lignin with more than 50 megatons of lignin produced annually at commercial scale. However, most is burned to produce energy, which alternatively could be used to make useful chemicals. A major issue with producing chemicals from lignin though is that the properties of lignin vary from source to source and from season to season. Such variability can affect the yield and quality of the chemicals produced from lignin. In a TU/e-led study, researchers have developed and tested a new and efficient model to predict the yield of lignin with specific chemical properties that are important to produce biobased chemicals, materials, or fuels. The research was published last September in the journal Green Chemistry. To date, most lignin derived from sources such as agricultural waste materials or woody biomass is burned to produce energy. As a renewable raw material, this can be seen as a waste. Researchers are looking for ways to use organic lignin as a reliable raw material for the chemical industry to make resins, foams, and biofuels. As a source, woody biomass can be grown relatively fast, and thus it pro vides easy access to lignin for the long-

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term production of chemicals. According to Mark Vis, assistant professor in the Department of Chemical Engineering and Chemistry research lead of the new study, this is an idealized view of the situation though. According to him the major problem is that the properties of lignin are both unpredictable and variable, and this affects its usability.

The right type

So, why is the unpredictability of lignin properties a bad thing? Vis explains: ‘Let’s say that we want to make a certain chemical using lignin, but we need lignin with a specific chemical composition to make the chemical. In any sample of lignin, there could be a million distinct types of lignin units, and isolating the right lignin type to make the chemical is the heart of the problem. Lignin does not have a single well-defined chemical

INNOVATIVE MATERIALS structure, in contrast to the raw materials used to make conventional chemicals.’

New model

A treatment process known as solvent fractionation can help isolate the desired lignin types whereby lignin types with desired chemical properties are dis solved using a solvent, which later can be purified further by removing them from the solvent. ‘Fractionation can decrease the range of lignin types, but with millions of lignin types in a sample, it’s difficult to be sure that a particular solvent will isolate a particular type of lignin,’ says Vis. ‘Theoretical calculations can help predict the outcome of fractionation, but current theories are too complex to apply to lignin. And this is the problem that we solved.’ The solution from Vis and his collaborators at TU/e (including first author Stijn van Leuken and postdoc Dannie van Osch), Maastricht University, and the spin-off Vertoro is a new model that accurately and quickly predicts the fractionation of lignin in a solvent blend containing methanol and ethyl acetate. As it turns out, a blend is better for isolating precisely the lignin fraction needed. The researchers’ model is based on the Flory-Huggins solution theory, a famous mathematical way of quantifying polymer solubility. Usually, this model is applied to study how one polymer interacts with a solvent, but the researchers took the model a number of steps further. Vis: ‘Our model is well suited if you have hundreds of different polymer types simultaneously, which means that we can model the interactions of numerous lignin polymer types with different chemical properties (such as polymer chain length and composition) with the solvent. Gaining insight on these interactions is critical as they affect whether a certain lignin type will dissolve or not in a certain solvent.’

Validation

To validate the new model, the research ers calculated the fractionation of lignin derived from wheat straw and then compared the model data with experiments involving the same materials. The model

Reactor bij de TU/e (lab van Emiel Hensen)

was tested on existing data related to a common industrial lignin in a different solvent blend (methanol and dichloromethane). The model was applied with minimal effort, and described the data very well. To date, in terms of using numerical tools to predict lignin yields, it’s all quite speculative. ‘Not many people are using theory to predict yields,’ says Remco Tuinier, professor in the Department of Chemical Engineering and Chemistry and also an author on the paper. ‘Our model makes it easy and possible to predict which lignin can be isolated with a certain solvent (mixture). It’s a significant development for the field.’

Next steps

With the model proving so successful in predicting lignin yields, how can this model make an impact in industry? Panos Kouris, Chief Technology Officer and co-founder of Vertoro and co-author of the paper: ‘This model is now a stepping stone for all lignin valorization activities; both in academia and industry.’ Vertoro is a spin-off company from a public-private partnership including TU/e, and wants to offer viable and affordable biobased alternatives to fossil resources, so Kouris and his colleagues are well aware of the impact that the model can have on both academia and industry. Kourdis: ‘In academia, the model can

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INNOVATIVE MATERIALS

Mark Vis (Foto: TU/e)

Panos Kouris (Foto: TU/e)

instigate new research lines on new solvents and lignin types, in addition to looking at ways to target particular lignin chemical properties for particular applications,' notes Kouris. 'And in the biomass biorefining industry, the model could be very insightful and contribute to the design of new lignin-based products.’

Getting ready

In theory, the model can already be used by biorefineries to explore the valorization of certain lignin types, but there’s still a lot to be done before the model is ready for large-scale commercial use. First, the model needs to be validated for the most common lignin types pro-

cessed by the industry. Next, the solvent fractionation technology itself must have reached the level where the technology is ready for commercial use, and finally, clear applications of the final products are needed in the market, such as biobased packaging or biofuels. Satisfying these requirements will take time, yet Kouris and his colleagues at Vertoro are optimistic that the model will have an impact on biorefineries sooner rather than later. Vertoro expects that in the first half of 2024, the model will be extended to test several commercially available lignin sources, especially from second-generation cellulosic ethanol biorefineries that are actively looking for lignin valorization technologies and solutions. This work was published last September in Green Chemistry onder de titeled ‘Quantitative Prediction of the Solvent Fractionation of Lignin’, Stijn van Leuken et al. It's online> Text: TU/e

MaterialDistrict Utrecht 2024 The 16th edition of MaterialDistrict Utrecht will take place from 6 to 8 March 2024 in Werkspoorkathedraal, Utrecht. With 125 exhibitors, a materials exhibition of 250 materials and a lecture programme with 50 speakers, the materials event for (interior) architects and R&D professionals is completely devoted to material innovations for the spatial domain: Architecture, Interior, Garden & Landscape Architecture, Leisure , Exhibition & Decor Construction and Furniture & Interior Construction.

More at MaterialDistrict: https://utrecht.materialdistrict.com

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RESEARCH

Self-disinfecting gloves burn viruses but is safe for skin A team of scientists from Rice University developed a new material that heats up so much on the outside that it kills viruses but at the same time remains cool on the inside. According to Rice, the material could play an interesting role in the development of personal protective equipment (PPE) in future. The composite, a textile-based material, uses Joule heating to decontaminate its surface of coronaviruses like SARS-CoV-2 in under 5 seconds, effectively killing at least 99.9% of viruses. Wearable items made from the material can handle hundreds of uses with the potential for a single pair of gloves to prevent at least

Daniel Preston (from left), Kai Ye, Yizhi Jane Tao and Marquise Bell (Photo by Gustavo Raskosky/Rice University)

A glove made of a material designed at Rice University that kills coronaviruses with heat without burning users’ skin (Photo: Gustavo Raskosky/Rice University)

ten kilos of waste of waste that would have resulted from discarded single-use nitrile medical gloves. The best part is you don’t even need to take off the gloves or other protective garments to clean them. This material allows you to decontaminate in seconds, so you can get back to the task at hand. Using electrical current, the material rapidly heats up its outer surface to temperatures above 100 °C, while remaining close to normal body temperature on the reverse side near the user’s skin where it reaches a maximum of about 36 °C. Compared to other decontamination methods, dry heat tends to be both

reliable and less likely to damage protective equipment. Considering the temperature difference between its outer and inner surfaces, the material is surprisingly supple and lightweight. The research was published last September in Applied Materials and Interfaces under the title 'Rapid In Situ Thermal Decontamination of Wearable Composite Textile Materials' (https://doi. org/10.1021/acsami.3c09063). More at Rice>

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INNOVATIVE MATERIALS

Lithium on a string

The researchers constructed an array of lithium-harvesting strings to demonstrate the scalability of their technique (Photo: Bumper DeJesus, Andlinger Center for Energy and the Environment)

Researchers at Princeton have developed an extraction technique that slashes the amount of land and time needed to produce lithium, a vital component of the batteries at the heart of electric vehicles and energy storage for the grid. The researchers say their system can improve production at existing lithium facilities and unlock sources previously seen as too small or diluted to be worthwhile. Lithium is key to a clean energy future. But producing the silvery-white metal comes with significant environmental costs. Among them is the vast amount of land and time needed to extract lithium from briny water, with large operations running into the dozens of square miles and often requiring over a year to begin production. And there's another problem: the limited supply of lithium is one obstacle to the transition to a low-carbon society. The core of the new extraction technique is a set of porous fibers twisted into strings, which the researchers engineered to have a water-loving core and a water-repelling surface. When the ends are dipped in a salt-water solution, the water travels up the strings through capillary action - the same process trees use to draw water from roots to leaves. The water quickly evaporates from

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each string’s surface, leaving behind salt ions such as sodium and lithium. As water continues to evaporate, the salts become increasingly concentrated and eventually form sodium chloride (table salt) and lithium chloride crystals on the strings, allowing for easy harvesting. In addition to concentrating the salts, the technique causes lithium and sodium to crystallize at distinct locations along

the string due to their different physical properties. Sodium, with low solubility, crystallizes on the lower part of the string, while the highly soluble lithium salts crystallize near the top. The natural separation allowed the team to collect lithium and sodium individually, a feat that otherwise requires the use of more chemicals.

INNOVATIVE MATERIALS the accelerated evaporation rate could also allow for operation in more humid climates. They are even investigating whether the technology would allow for lithium extraction from seawater. The results of this work were published last September in Nature Water titled ‘Spatially Separated Crystallization for Selective Lithium Extraction from Saline Water’. This research was supported by the Princeton Catalysis Initiative, Princeton’s Imaging and Analysis Center, the Andlinger Center for Energy and the Environment, and the National Science Foundation (NSF-MRSEC DMR-2011750). Much more at Princeton>

Meiqi Yang, a graduate student in civil and environmental engineering and one of the study’s lead authors, operates the innovative approach to lithium extraction (Photo: Bumper DeJesus, Andlinger Center for Energy and the Environment)

Evaporation pond on a string

Conventional brine extraction involves building a series of huge evaporation ponds to concentrate lithium from salt flats, salty lakes or groundwater aquifers. The process can take anywhere from several months to a few years. The operations are only commercially viable in a handful of locations around the world that have sufficiently high starting lithium concentrations, an abundance of available land and an arid climate to maximize evaporation. For instance, there is only one active brine-based lithium extraction operation in the United States, located in Nevada and covering more than seven square miles. The Princeton method is much more compact and can produce lithium much faster. Once scaled up, the researchers expect that ninety percent less space will be required to achieve the current level of production. Moreover, the new process is twenty times faster. The string technique is far more compact and can begin producing lithium much more quickly. Furthermore, a compact, cheap and

rapid process can identify new sources of lithium, such as disused oil and gas wells and geothermal salt wells, which are currently too small or too dilute for lithium extraction. The researchers said

Video byBumper DeJesus, Andlinger Center for Energy and the Environment

The classical extraction of lithium There are roughly three classic methods to extract lithium. The most common process is evaporation, in which a basin is filled with lithium-containing brine, after which some of the water evaporates by the sun and wind. Sodium chloride, which is less soluble than lithium chloride, partly precipitates and is removed. With the remaining dissolved lithium chloride, the process is repeated several times, making the salt solution increasingly more concentrated. The sodium/lithium ratio in the solution increasingly shifts towards lithium. A second method is filtration using a lithium-lanthanum-titanium oxide (LLTO) membrane, which allows lithium ions to pass through. This method does require energy. One kg of lithium requires approximately 76 kWh of energy, which in return releases chlorine and hydrogen as by-products. The third method is extraction. An extraction agent (often titanium acid) is added to brine that selectively binds lithium ions. Once an equilibrium has been established, the extraction agent is filtered out of the brine and regenerated.

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INNOVATIVE MATERIALS

Plasma against PFAS

Harmful PFAS chemicals in both soil and surface water are a growing problem. Removing them using conventional filter techniques is costly and almost infeasible. Researchers at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB are now successfully implementing a plasma-based technology in the AtWaPlas joint research project. Contaminated water is fed into a combined glass and stainless-steel cylinder where it is then treated with ionized gas, i.e. plasma. This reduces the PFAS molecular chains, allowing the toxic substance to be removed at a low cost. Per- and polyfluoroalkyl substances (PFAS) have many special properties. As they are thermally and chemically stable as well as resistant to water, grease, and dirt, they can be found in many everyday products: pizza boxes and baking paper are coated with them, for example, and shampoos and creams also contain PFAS. In industry they serve as extinguishing and wetting agents, and in agriculture they are used in plant protection products. However, traces of PFAS are now also being detected where they should not be found in soil, rivers, and groundwater, in food and in drinking water. This is how the harmful substances end up in the human body. Due to their chemical stability, eliminating these so-called ‘forever chemicals' has been almost impossible up to now without considerable effort and expense.

The research team led by Dr. Georg Umlauf, an expert in functional surfaces and materials, utilizes plasma’s ability to attack the molecular chains of substances. The electrically conductive gas consisting of electrons and ions is generated when high voltage is applied.

Plasma

The AtWaPlas joint research project aims to change that. The acronym stands for Atmospheric Water Plasma Treatment. The innovative project is currently being run at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB in Stuttgart in cooperation with the industrial partner HYDR.O. Geologen und Ingenieure GbR from Aachen. The aim is to treat and recover PFAS-contaminated water using plasma treatment.

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The plasma atmosphere is clearly visible in the reactor through the characteristic glow and flashes of light (Photo: Fraunhofer IGB)

INNOVATIVE MATERIALS The AtWaPlas technology, on the other hand, is capable of eliminating the harmful substances without any residue and is according to Fraunhofer very efficient and low maintenance.

Real samples

In order to ensure true feasibility, the Fraunhofer researchers are testing the plasma purification under more challenging conditions. Conventional test methods involve using perfectly clean water and PFAS solutions that have been synthetically mixed in the laboratory. However, the research team in Stutt gart is using 'real' water samples that come from PFAS-contaminated areas. The samples are collected by the project partner HYDR.O. Geologen und Ingenieure GbR from Aachen. The company specializes in cleaning up contaminated sites and also carries out hydrodynamic simulations. The real water samples that Umlauf and his teamwork with therefore contain PFAS as well as other particles, suspended solids and organic turbidity. This plasma method can also be used to break down other harmful substances, including pharmaceutical residues in wastewater, pesticides and herbicides, but also industrial chemicals such as cyanides. AtWaPlas can also be used to treat drinking water in mobile applications in an environmentally friendly and cost-effective way.

Pilot plant for the elimination of PFAS. Following the initial success of the trials, the technology is now to be optimized and scaled up for practical applications on an industrial scale (Photo: Fraunhofer IGB)

The German Federal Ministry of Education and Research (BMBF) is funding the ‘AtWaPlas’ project within the ‘KMU-innovativ: Ressourceneffizienz und Klimaschutz’ funding measure, as part of the federal research program on water ‘Wasser: N’, which contributes to the BMBF ‘Research for Sustainability’ (FONA) Strategy’. More at Fraunhofer IGB>

Fraunhofer researchers are using a cylindrical construction for this plasma process. Inside is a stainless-steel tube, which serves as the ground electrode of the electrical circuit. The outer copper mesh then acts as a high-voltage electrode and is protected on the inside by a nonconductive, glass dielectric (https://en.wikipedia.org/wiki/Dielectric). A very small gap is left between the two, which is filled with an air mixture. This air mixture is converted into plasma when a voltage of several kilovolts is applied. It is visible to the human eye by its characteristic glow and discharge as flashes of light.

Closed circuit

During the purification process, the PFAS-contaminated water is introduced at the bottom of the stainless-steel tank and pumped upwards. It then travels down through the gap between the electrodes, passing through the electrically active plasma atmosphere. The plasma breaks up and shortens the PFAS molecule chains as it discharges. The water is repeatedly pumped through both the steel reactor and the plasma discharge zone in a closed circuit, reducing the PFAS molecule chains further each time until they are completely mineralized. The technology developed at the Fraunhofer Institute has a key advantage over conventional methods such as active carbon filtering. Active carbon filters can bind the harmful substances, but they are unable to eliminate them. This means that the filters must be replaced and disposed of regularly.

Plasma reactor: Plasma is created by applying voltage to the copper electrode. Contaminated water is pumped upwards and flows back down through a gap in the plasma discharge zone, attacking the PFAS in the process (Illustration: Fraunhofer IGB)

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INNOVATIVE MATERIALS

How to make color-changing ‘Transformers’ with polymers Shape and color changing are key survival traits for many animals. Chameleons can change their body to hide from predators, to reflect their moods, or even to defend their territory, while some soft-bodied animal-like octopuses, squids, and cuttlefish can change both their color and shape to signal or camouflage. Mimicking these capabilities using artificial polymer materials holds great potential in sensing, soft robotics, and the fashion and art industries. During her research, PhD candidate Pei Zhang has realized some incredible colour changing and shape morphing abilities in polymer materials. Pei Zhang defended her PhD thesis at the department of Chemical Engineering and Chemistry on August 31st.

As part of her PhD research, Pei Zhang has developed versatile techniques for the fabrication of so-called liquid crystal elastomers, or LCEs for short, that exhibit both structural colour changes and shape morphing properties similar to those seen in animals such as chameleons and octopuses. The LCEs developed by Zhang and her colleagues respond to various external

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stimuli such as changes in temperature, mechanical deformation through stretching, and changes in illumination.

Coatings

For her research, Zhang fabricated temperature responsive cholesteric LCE coatings and created structural colour patterns in these coatings. The structural colour originates from the periodical

structure of the material, which reflects light. Pigment was not added to achieve this effect. By placing another soft polymer carrier layer on top of the LCE coatings these cholesteric LCE thin films can be manually stretched. Upon stretching, these films then exhibit a colour change from orange to blue. The structural colour of the pattern is

INNOVATIVE MATERIALS prepared so that it reflects the near-infrared spectrum when the film is unstretched. This means that the structural colour is not visible to the human eye. The material only reveals a pre-programmed pattern once it is stretched, whereby the reflected light wavelength shifts to the visible spectrum and the pattern then becomes visible. This process is known as mechanochromism. This remarkable material holds great potential when applied as a mechanochromic ‘sticker’ to detect the deformation of a substrate. For instance, it offers direct visual feedback, making it suitable for applications in medical textiles to monitor the pressure applied on wounds as well as in ceilings and windows to monitor safety conditions in buildings. Zhang also created a 3D-shaped ‘beetle’ and a 3D-shaped ‘cuttlefish’ that adjust their colour from green to red when heated and their body shape when exposed to near-infrared light. In nature, some beetles can change their body colour and Zhang has now shown that it is feasible to recreate this phenomenon in plastic. In addition, she created a 3D 'squid' created to mimic both shape and colour adaptations observed in various molluscs.

The methods used to fabricate structurally colored LCEs in Zhang’s work form the basis for a versatile toolbox for the design and production of functional polymer materials.

Future

In terms of the future use of these materials, Zhang sees a number of possibilities. The materials she has developed could be used, for instance, in soft robotics and as strain sensors in smart textiles. According to Zhang this could add more visual interactivity to a product, which could improve the user experience and accessibility with a product. Moreover, incorporating these materials in the fashion industry is another exciting opportunity, such as crafting responsive jewelry that adapts its appearance based on the wearer’s requirements. The PhD-thesis 'Structurally Colored Liquid Crystal Elastomer Actuators' can be found here> Original text: TU/e>

Pei Zhang

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INNOVATIVE MATERIALS

Nanoscale 3D printing of metals Late last year, Caltech University researchers revealed that they had developed a new fabrication technique for printing microsized metal parts containing features about as thick as three or four sheets of paper. The team recently presented the technique that allows objects to be printed a thousand times smaller: 150 nanometers, comparable to the size of a flu virus. The work was conducted in the lab of Julia R. Greer, the Ruben F. and Donna Mettler Professor of Materials Science, Mechanics and Medical Engineering; and Fletcher Jones Foundation Director of the Kavli Nanoscience Institute. It is described in a paper appearing in the journal Nano Letters. The process starts with preparing a photosensitive ‘cocktail’ that is largely comprised of a hydrogel, a kind of polymer that can absorb many times its own weight in water. This cocktail is then selectively hardened with a laser to build a 3D scaffold in the same shape as the desired metal objects. In this research, those objects were a series of tiny pillars and nanolattices. The hydrogel parts are then infused with

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an aqueous solution containing nickel ions. Once the parts are saturated with metal ions, they are baked until all the hydrogel is burned out, leaving parts in the same shape as the original, though shrunken, and consisting entirely of metal ions that are now oxidized (bound to oxygen atoms). In the final step, the oxygen atoms are chemically stripped out of the parts, converting the metal oxide back into a metallic form.

The research team discovered that the process does not exactly produce what appears to be an optimal material. All kinds of thermal and kinetic processes take place simultaneously during the process, leading to a messy microstructure. Defects such as pores and irregularities in the atomic structure are formed, which are generally considered as strength deteriorating defects. If a large metal object, such as an engine block,

INNOVATIVE MATERIALS

The irregular interior structure of a nanoscale nickel pillar (Photo: Caltech)

A nanoscale lattice prepared using a new technique developed by the lab of Julia R. Greer. The image was produced by an electron microscope (Photo: Caltech)

had such an irregular microstructure, it would be significantly weak. But to their surprise, the researchers saw exactly the opposite. The many defects that would weaken a metal part on a larger scale turned out to strengthen the nano parts. The researchers think that the application of their new technique could

be particularly interesting for making components, such as catalysts for hydrogen; storage electrodes for carbon-free ammonia and other chemicals; and essential parts of devices such as sensors, microrobots and heat exchangers. The paper describing the work, ‘Suppressed Size Effect in Nanopillars with

Hierarchical Microstructures Enabled by Nanoscale Additive Manufacturing,’ was published last August in Nano Letters. Much more at Caltech>

Mechanical engineering graduate student Wenxin Zhang works in the nano-fabrication lab (Photo: Caltech)

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RESEARCH

3D printed, compositionally graded alloys for extreme environments Scientists at the Department of Energy's Oak Ridge National Laboratory (ORNL) have developed a new technique for making materials consisting of non-weldable superalloys combined with refractory alloys. The result is a graded, composite material that transition seamlessly from high-strength superalloys to refractory alloys. And that, without welding. According to the ORNL scientists the key to this process lies in the ‘secret sauce‘ in this case a powder. The scientists used powders of Inconel 718, a nickel-based alloy, and C103, a niobium-based alloy. These alloys - one high strength and the other high-temperature resistant - do not want to join and tend to create cracks when they do. By using a special 3D printing, deposition technique (Directed Energy Deposition, DED) and changing the speed at which the powders flow, the scientists can change the composition of the joined metals so that it has the beneficial properties of both. According to the ORNL-scientists, the potential applications for this technology are vast, including rocket engines,

(Photo: Brian Jordan, Soumya Nag, ORNL/VS Energy Department)

aerospace manufacturing, fusion and fission reactor fabrication, marine-related uses, and renewable energy systems - essentially any field where extreme environments exist.

Directed Energy Deposition (DED) works by depositing multifunctional material on a specific surface where it solidifies, causing materials to fuse to form a structure. DED machines use a nozzle mounted on a multi-axis arm that can move in multiple directions, allowing for variable deposition. The process is typically performed in a controlled chamber with reduced oxygen levels or under an inert gas (argon in the case of the ORNL study). DED uses a heat source to melt a powder or wire while

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A provisional patent application has now been submitted regarding the materials used and the production process. More at ORNL>

it is stored on the surface of an object. The material is added layer by layer and solidifies from the molten pool. Layers are typically 0.25mm to 0.5mm thick. The cooling times for materials are very fast, around 1000-5000 °C per second.

RESEARCH

Publications Application of biochar in concrete - A review Cement and Concrete Composites, October 2023

The continuous rise in global temperatures is an evidence of climate change. CO2 emissions have caused major problems owing to its contribution to climate change. In particular, the construction industry has a considerable carbon footprint. Therefore, investigations into climate change mitigation are indeed a priority. All steps in the construction process, from raw materials preparation to cement production, contribute to CO2 emissions. This can be mitigated to a certain extent by incorporating bio-based constituents into construction materials. However, bio-based materials may negatively affect cement reaction and structural performance, despite their positive environmental impacts. Biochar, a carbon-rich product of biomass pyrolysis, is considered a potential substitute for cement replacement that can enhance structural properties if used in appropriate amounts. Although biochar has conventionally been used as a soil amendment in the agricultural industry, researchers have recently investigated its applicability in concrete. Importantly, the results thus far have reported its contribution to the enhancement of the mechanical, thermal, and physical properties of cement. This review provides a comprehensive overview of the physicochemical properties of biochar added cementitious materials, including the fresh and hardened properties of biochar-cement mixtures considering both environmental and economic aspects. The article is online>

Enhanced uranium extraction selectivity from seawater using dopant engineered layered double hydroxides Energy Advances, Volume 8 2023

Although the concentration of uranium (U) in seawater is extremely low (3.3 μg L−1), the total amount of U in Earth's oceans is more than one thousand times greater than the amount in terrestrial ores. To extract useable quantities of U from seawater, highly selective adsorbent materials are needed since competing elements (e.g. sodium, calcium) are present at orders of magnitude higher concentrations. Layered double hydroxide (LDH) materials are an intriguing adsorbent material for U seawater extraction, as they are simple to prepare and can incorporate multiple metal chemistries to modulate structure and properties. Herein, X-ray absorption spectroscopy (XAS) is used to provide fundamental insight into the adsorption mechanism of U extraction from seawater and

how doping of trivalent lanthanides into MgAl LDH materials can enhance their selectivity. It is revealed that the mechanism of U sorption from U-spiked seawater is primarily surface complexation with abundant Mg/Al–OH sites, along with the ion exchange mechanism whereby interlayer nitrate is replaced by anionic species (carbonate, hydroxyl and uranyl carbonate). Further, lanthanide doping increased the ionic character of bonding within the LDH and hence the selectivity for binding U via surface sorption. Neodymium doped LDH exhibited superior U selectivity to state-of-the-art amidoxime functionalised polymers, as well as adsorption capacity and kinetics comparable to these state-of-the-art adsorbents. These findings indicate that dopant engineering of LDHs provides a simple, effective method for controlling selectivity and producing adsorbents capable of challenging separations such as U extraction from seawater. The article is online>

Chemical Upcycling of PET into a Morpholine Amide as a Versatile Synthetic Building Block ACS, August 2023

A catalytic chemical upcycling methodology for polyesters has been developed. Commodity polyesters, such as polyethylene terephthalate (PET), are depolymerized with morpholine by using a Cp*TiCl3 catalyst under ambient pressure without any additives, which provides morpholine amides exclusively. The method can also apply to other polyesters, polybutylene terephthalate (PBT), polyethylene adipate (PEA), polybutylene adipate (PBA), and polybutylene succinate (PBS), as well as an actual PET waste of a 50 g postconsumer beverage bottle. The product, morpholine amide, is a versatile building block in organic chemistry, and the synthetic utility has thus been demonstrated by further transformations, such as hydrolysis, selective reductive conversions, and Grignard reaction. The article is online>

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RESEARCH Study of screwed bamboo connection loaded parallel to fibre Construction and Building Materials, September 2023

A method for connecting unfilled natural bamboo was pro posed, comprising screws and metal plates. The method is commonly used in timber connections, yet in bamboo connections screws are rarely seen, mostly due to the perceived risk of splitting. This study aimed to assess the applicability of screws in bamboo through extensive testing of short-term laterally loaded connection parallel to fibre, including variation of several parameters. An existing timber model was found to be appropriate to estimate the connection yield capacity. In terms of the environmental benefits, connection capacity, stiffness and ductility, the method appears to be an attractive alternative to the common mortar-infilled bolted bamboo connection. The risk of splitting was found to be low provided appropriate spacing parallel and across fibre between screws is provided. The main outcome of the study is the design guidance for the proposed connection, including spacing rules and prediction of the connection capacity. The article is online>

Besides, it possessed a good thermal stability and self-adaptability, as well as solvent resistance and chemical degradability. This work provides a promising method to fabricate fully bio-based plastics as alternative to petroleum-based plastics. The article is online>

Microelectronic Morphogenesis: Smart Materials with Electronics Assembling into Artificial Organisms

Advanced Materials, October 2023

Microelectronic morphogenesis is the creation and maintenance of complex functional structures by microelectronic information within shape-changing materials. Only recently has in-built information technology begun to be used to reshape materials and their functions in three dimensions to form smart microdevices and microrobots. Electronic information that controls morphology is inheritable like its biological counterpart, genetic information, and is set to open new vistas of technology leading to artificial organisms when coupled with modular design and self-assembly that can make reversible microscopic electrical connections.

Examples of bamboo bolted connections (Coffee region, Colombia)

Flexible, thermal processable, self-healing, and fully bio-based starch plastics by constructing dynamic imine network Green Energy & Environment, August 2023

The serious environmental threat caused by petroleum-based plastics has spurred more researches in developing substitutes from renewable sources. Starch is desirable for fabricating bioplastic due to its abundance and renewable nature. However, limitations such as brittleness, hydrophilicity, and thermal properties restrict its widespread application. To overcome these issues, covalent adaptable network was constructed to fabricate a fully bio-based starch plastic with multiple advantages via Schiff base reactions. This strategy endowed starch plastic with excellent thermal processability, as evidenced by a low glass transition temperature (Tg = 20.15 °C). Through introducing Priamine with long carbon chains, the starch plastic demonstrated superior flexibility (elongation at break = 45.2%) and waterproof capability (water contact angle = 109.2°).

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Characterization of various modular functional technologies with respect to living systems on three axes: size, amount of information processing, and shape flexibility. For size, the largest dimension in the completely folded state was employed. For information processing, both the amount of information per module and the number of specific operations performed per second were considered. For functional flexibility in shape-changing, the researchers used the % of size that the resting shape can be strained to implement a function. SMARTLETs (see definition in Scheme 1) is the generic acronym for the general class of modules with the full functionality to support microelectronic morphogenesis - their information processing becomes competitive using tiny CMOS electronic chiplets (see text) without impacting functional flexibility

Three core capabilities of cells in organisms, self-maintenance (homeostatic metabolism utilizing free energy), self-containment (distinguishing self from nonself), and self-reproduction

RESEARCH (cell division with inherited properties), once well out of reach for technology, are now within the grasp of information-directed materials. Construction-aware electronics can be used to proof-read and initiate game-changing error correction in microelectronic self-assembly. Furthermore, noncontact communication and electronically supported learning enable one to implement guided self-assembly and enhance functionality. Here, the fundamental breakthroughs that have opened the pathway to this prospective path are reviewed, the extent and way in which the core properties of life can be addressed are analyzed, and the potential and indeed necessity of such technology for sustainable high technology in society is discussed.

that is 3D printed into complex structures and converted to silica glass via deep ultraviolet (DUV) irradiation in an ozone environment. The unique DUV-ozone conversion process for silica microstructures is low temperature (~220°C) and fast (<5 hours). The printed silica glass is highly transparent with smooth surface, comparable to commercial fused silica glass. This work enables the creation of arbitrary structures in silica glass through photochemistry and opens opportunities in unexplored territories for glass processing techniques. The article is online>

The article is online>

Recycling greenhouse gases into a specific product Nature Communications, May 2023

Low-temperature 3D printing of transparent silica glass microstructures Science Advances, October 2023

Transparent silica glass is one of the most essential materials used in society and industry, owing to its exceptional optical, thermal, and chemical properties. However, glass is extremely difficult to shape, especially into complex and miniaturized structures. Recent advances in three-dimensional (3D) printing have allowed for the creation of glass structures, but these methods involve time-consuming and high-temperature processes.

Electrochemical CO2 reduction (CO2R) is an approach to closing the carbon cycle for chemical synthesis. To date, the field has focused on the electrolysis of ambient pressure CO2. However, industrial CO2 is pressurized - in capture, transport and storage - and is often in dissolved form. It was discovered that pressurization to 50 bar steers CO2R pathways toward formate, something seen across widely-employed CO2R catalysts. By developing operando methods compatible with high pressures, including quantitative operando Raman spectroscopy, the high formate selectivity could be to increased CO2 coverage on the cathode surface. The interplay of theory and experiments validates the mechanism, and guides us to functionalize the surface of a Cu cathode with a proton-resistant layer to further the pressure-mediated selectivity effect. This work illustrates the value of industrial CO2 sources as the starting feedstock for sustainable chemical synthesis. The article is online>

A 3D printed glass microfluidic channel, shown hollow and filled with liquid (Credit: Georgia Institute of Technolog)

Here, a photochemistry-based strategy is proposed for making glass structures of micrometer size under mild conditions. The new technique uses a photocurable polydimethylsiloxane resin

Under specific pressurized conditions, carbon dioxide can be catalytically transformed into formate in a high-pressure narrow-gap aqueous flow cell (Image Credit: 2023, Huang et al.)

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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

•

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

Video: How Enterprise Europe Network works

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 Materials contact Nils Haarmans: T: +31 (0) 88 062 5843 M: 06 21 83 94 57 nils.haarman@rvo.nl More information websites can be found at the Europe Network websites: www.enterpriseeuropenetwork.nl http://een.ec.europa.eu

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EVENTS Sustainable packaging summit 2023 14 - 15 November 2023, Amsterdam

Silicone expo Europe 2024 28 - 29 February 2024, Amsterdam

Beton event & Experience 2023 16 November 2023, Rotterdam

Internationale Eisenwarenmesse 3 - 6 March 2024, Cologne

Vakbeurs Recycling 21 - 23 November 2023, Gorinchem

JEC World 2024 5 - 7 March 2024, Paris

Hagener Symposium Pulvertechnologie 24 - 25 November 2023, Hagen

MaterialDistrict Utrecht 2024 6 - 8 March 2024, Utrecht

The Advanced Recycling Conference 2023 28 - 29 November 2023, Cologne

BLE.CH 2024 13 - 15 March 2024, Bern

Münchener Forum Verbindungstechnologie 29 - 30 November 2023, Unterhaching

Cellulose Fibres Conference 2024 13 - 14 March 2024, Cologne

ARCHITECT@WORK Düsseldorf 6 - 7 December 2023, Düsseldorf

Fensterbau Frontale 19 - 22 March 2024, Nuremberg

EBC 23 - The European Bioplastics Conference 2023 12 - 13 December 2023, Berlin

Silicon PV 2024 15 - 19 April 2024, Chambery

Materialen NL Conference 12 December 2023, Arnhem

Maintenance Gorinchem 16 - 18 April 2024, Gorinchem

EUROGUSS 16 - 18 January 2024, Nuremberg

Ceramitec 23 - 26 April 2024, Munich

Batibouw 2024 17 - 25 February 2024, Brussels

Schweissen 2024 23 - 26 April 2024, Wels

Maintenance Dortmund 2024 21 - 22 February 2024, Dortmund

Intermat 2024 24 - 27 April 2024, Paris

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Hét expertisecentrum voor materiaalkarakterisering. Integer, onafhankelijk, objectief onderzoek en advies. ISO 17025 geaccrediteerd. 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

TCKI adv A5 [ZS-185x124] Chemische analyse 14.indd 1

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