Disorder can have its advantages: Bernhard C. Bayer will produce "high-entropy materials- as thin 2D layers. For this project, he is now receiving an ERC Consolidator Grant.
In materials science, things are not always absolutely clean and controlled: In so-called "high-entropy materials", several different types of atoms are used, which mix and arrange themselves quite randomly without a fixed pattern. It is precisely this randomness that makes it possible to achieve very specific material properties.
Bernhard Bayer and his team at TU Wien now want to transfer these findings to the science of 2D materials - i.e. apply them to ultra-thin layers that consist of only one or a few atomic layers. Such a combination of high-entropy materials and 2D materials has not been studied before, and the technique opens up interesting new possibilities for electronics or novel catalysts. To implement this idea, Bernhard Bayer has now been awarded an ERC Consolidator Grant, endowed with 2 million euros - one of the most highly endowed and prestigious grants in the European research landscape.
Mixing atomic species
Mixing different types of atoms to create novel materials properties is nothing new: metallic alloys have been produced for thousands of years, and in the semiconductor industry different materials are doped, i.e. single foreign atoms are added that fundamentally change the electronic behaviour of the material. Many materials consist of one or two basic elements, which are then modified by small amounts of additives - such as steel, which consists of iron with a little bit of added carbon.
What is new, however, is "entropy engineering", which is used today for both metallic alloys and ceramic materials. In this process, several different chemical elements are combined in similar quantities. There is no longer a dominant type of atom in which all the others are embedded, but the entire structure is a rather messy-looking mix of different chemical elements.
"This is exactly how new functional properties can be achieved," says Bernhard Bayer. "You create materials with very high internal entropy, the individual positions in the crystal lattice are randomly occupied by different atoms, and this is precisely what allows us to stabilise configurations that enable new material properties."
Great success has also been achieved recently with so-called 2D materials, such as graphene, which consists of only a single layer of carbon atoms. Bernhard Bayer now wants to combine these two promising areas of research and produce high-entropy 2D materials.
"Furthermore, by going to 2D materials, we want to make processes such as diffusion or crystallisation in such high-entropy materials visible for the first time by high-resolution microscopy methods," says Bernhard Bayer. The aim is to find out how such materials can be used for electronics or as catalysts that enable certain chemical reactions.
Graz, Cambridge, Vienna
Bernhard C. Bayer first studied at the Graz University of Technology and then went to the University of Cambridge, where he completed his Master’s degree and then his doctorate. With a prestigious Marie Sklodowska Curie Fellowship from the European Commission, he returned to Austria in 2014 and did research at the Faculty of Physics at the University of Vienna. In 2017 he joined TU Wien, where he was able to build up his own research team as a junior research group leader at the Institute of Materials Chemistry.