New Helmholtz Institute researches materials of the future
Polymers are the basic building blocks of plastics. The Helmholtz-Zentrum Berlin für Materialien und Energie (HZB) and Friedrich Schiller University Jena have founded an institute specializing in polymers. Together, researchers from the two institutions at the new Helmholtz Institute for Polymers in Energy Applications, or HIPOLE for short, want to use them to develop innovative materials for the energy transition. One of HIPOLE's goals, for example, is to replace the cobalt used in batteries, which is often extracted under precarious working conditions. “Polymers are not only as suitable as conventional materials in energy generation, but also in conversion and energy storage,” says Yan Lu. “They can actively drive the energy transition in many areas.” To develop just such materials, HZB and Friedrich Schiller University Jena have now pooled their expertise.
“At HIPOLE, we research special polymers,” explains the HZB researcher and vice speaker of the new institute, which she launched together with founding director Ulrich Schubert from the University of Jena. “We tailor their chains, functional groups and composition precisely to the intended use.” To identify the most promising polymer candidates, it is necessary to know how the structure will affect subsequent function. To do this, samples are prepared in different variations and tested for their properties, such as the stability of the organic redox polymer-based thin-film batteries. The results are then fed back into the search. The process is supported by an AI system and high-throughput experiments. Here, HIPOLE benefits from the synergies that the two partners bring to the new institute. “The university in Jena has a lot of experience in high-throughput synthesis of polymers,” says the researcher. “They have a robotic system that produces different samples from the basic materials in parallel by varying the mixing ratios of the basic materials and the synthesis parameters, such as temperature.”
HZB, in turn, brings its great expertise in studying materials and the processes that take place within them. Together with large-scale facilities such as the synchrotron, they can watch materials at work and understand what's happening inside. “There are about five institutes in the world working on polymers in all areas of energy research," she says. “HIPOLE is the only one of them with large-scale research facilities like a synchrotron that can directly observe the processes in the materials.”
Both the University of Jena and the HZB have been running projects on polymers for energy applications for a long time. That's why Yan Lu is confident that the combined forces will be able to present groundbreaking results in the coming years. “I see great potential in polymer-based redox flow batteries,” she reveals. “But I'm also pinning my hopes on printable batteries and solar cells.”
This is just a small sample of what polymers can do in energy technology. For example, there is a group that can repair damage to its structure. Such self-healing materials could, for example, extend the life of batteries, making them cheaper and more sustainable. Polymers could also have a bright future ahead of them in the hydrogen economy, serving, for example, as membranes for the synthesis of the lightest of all gases.
When it comes to sustainability, however, the polymers are not without problems either. “We're doing research to change that,” says the scientist. “Because today they are mainly made from fossil raw materials." But soon, the researchers hope, coal, gas and oil could be replaced by renewable energy, green hydrogen, biomass and carbon dioxide.
In all research projects, Yan Lu assures, an application-oriented approach is always chosen. “We always think about the application right from the start,” she says. “And ideally, the end result should be a prototype that can be further developed into a marketable product.” With its proximity to the University's Innovation Campus in Jena, the location was strategically chosen for this purpose, and HZB's Technology Transfer will also contribute its many years of experience to the new institute.
Polymers are very large molecules, so-called macromolecules, which consist of one or more basic building blocks strung together, the constitutional repeating units. These in turn are themselves made up of smaller molecules, the monomers. Often, a constitutional repeating unit is also a monomer. Polyethylene is an example of this. Sometimes, however, several monomers are involved. One example is polyethylene terephthalate, or PET for short, which is used to make many beverage bottles. The properties of a material are determined by a certain part of the molecule. Chemists call this the functional group. One example is the hydroxyl group, which gives alcohols their typical properties. Another is the amino group of amino acids.
In addition to man-made polymers such as PET, there are also natural polymers such as silk or cellulose. If carbon atoms form the framework of the chain, these are referred to as organic polymers. In the case of inorganic polymers, silicon or phosphorus, for example, take over the task of the carbon. A well-known representative of these is silicone. In view of the large number of possible monomers and functional groups, the variety of polymers seems almost limitless.