26 October 2023
For pioneering projects in the fields of cryo-electron microscopy and hydrogen research, not just one but two scientists from Forschungszentrum Jülich, Prof. Carsten Sachse and Prof. Karl Mayrhofer, have received a much-coveted European Research Council (ERC) Synergy Grant. Synergy Grants are among the most prestigious awards for researchers in Europe and they are only awarded to teams.
Prof. Carsten Sachse, together with research partners from Germany and Switzerland, has received an ERC Synergy Grant to develop a cryo-electron microscopy technique that will enable even more precise investigation of the 3D structure of molecules in tissue samples and biological cells. In another project, Prof. Karl Mayrhofer from the Helmholtz Institute Erlangen-Nürnberg for Renewable Energy (HI ERN), a branch office of Forschungszentrum Jülich, is cooperating with researchers from Denmark, Germany, and Switzerland to systematically search for durable catalyst materials for the production of hydrogen. Thousands of material combinations are to be tested simultaneously using a unique evolutionary approach.
ERC Synergy Grants support interdisciplinary research projects by outstanding established researchers that push the boundaries of knowledge and cannot be addressed by a single discipline alone. Out of 395 applications submitted, only 37 teams were selected consisting of two to four researchers, who will receive funding of up to € 10 million over a period of six years.
New technique for cryo-electron microscopy
Cryo-electron microscopy, or cryo-EM, has revolutionized the life sciences in recent years by making it possible to directly determine the 3D structure of proteins in their natural state. Nevertheless, for many molecules, especially those that play a role in neurodegenerative diseases such as Alzheimer's and Parkinson's, the resolution and contrast of established imaging techniques are still insufficient. As part of the 4D-BioSTEM project, which is being funded with a total of € 7.5 million, Prof. Carsten Sachse from Forschungszentrum Jülich, Prof. Knut Müller-Caspary from Ludwig-Maximilians-Universität München, and Prof. Henning Stahlberg from the Swiss École Polytechnique Fédérale de Lausanne and the University of Lausanne want to jointly take the technology to the next level.
"In the case of such a groundbreaking innovation, many major and minor technical questions need to be addressed, which can be solved much more quickly through interdisciplinary cooperation as part of the ERC Synergy Grants than would be possible in separate specialist communities," says a delighted Carsten Sachse, who conducts research and teaches at Forschungszentrum Jülich and Heinrich Heine University Düsseldorf.
This will be made possible by 4D scanning electron microscopy. The method has so far been used primarily in materials research and enables an even finer level of detail by combining spatial and diffraction information. To study frozen biological samples, the interdisciplinary team, which combines expertise in biological and physical electron microscopy, uses specialized hardware and simulations, and develops microscope operating routines and image reconstruction algorithms for optimum image resolution. In this way, proteins in brain samples could be studied much more precisely in the future and - unlike in the past - directly in frozen tissue samples.
4D scanning electron microscopy
In conventional cryo-electron microscopy, many thousands of snapshots of a sample are taken from different viewing directions using transmission electron microscopy, and are then combined to create a detailed three-dimensional image. 4D scanning electron microscopy, in contrast, scans objects line by line in tiny steps. For each individual pixel, an additional diffraction image is recorded. The result is thousands to millions of overlapping diffraction images, which are then converted back into an interpretable image using ptychographic algorithms. In the 4D-BioSTEM project, corresponding techniques for calculating biomolecules will be developed, for example. The procedure is very data- and compute-intensive. The goal is to extract the maximum signal from the noisy data. This is because biological samples typically respond extremely sensitively to the electron beams, so that only a limited dose is available for the investigation.
Search for durable catalysts for the production of hydrogen
Hydrogen is considered the energy carrier of the future. To produce it, catalysts are needed, some of which are exposed to extreme conditions. Previous electrocatalysts usually cannot withstand this for long - new materials are required that are both powerful and durable, and ideally do not contain any expensive and scarce elements.
To look for them specifically, Prof. Jan Rossmeisl from the Danish University of Copenhagen, Prof. Alfred Ludwig from Ruhr University Bochum, Prof. Karl Mayrhofer from HI ERN, and Prof. Dr. Matthias Arenz from the Swiss University of Bern are pooling their expertise in the DEMI project, which is being funded with € 10 million as part of the ERC Synergy Grant.
"Our data-driven, networking approach will make catalysts more stable and powerful. The goal is to make both water electrolysis and fuel cell operation more efficient," explains Karl Mayrhofer from HI ERN and Friedrich-Alexander Universität Erlangen-Nürnberg.
Materials consisting of five or more elements are particularly promising. The search is like looking for a "needle in a haystack", because there is an almost infinite number of possible connections. Using a unique evolutionary approach, thousands of promising combinations are first calculated and then tested simultaneously. The best materials that have proven themselves are then translated into applications.
Material research according to the principle of evolution
The Copenhagen researchers calculate promising material combinations using theoretical electrochemistry and simulations. They follow an evolutionary principle by making small changes and testing whether they have a positive or negative impact. In this way, the material becomes better and better. The Bochum team is conducting, for example, evolutionary screening with novel micromaterial libraries. Thousands of materials produced at the same time are then exposed to extreme electrochemical conditions in order to identify the ones that are "able to survive" very quickly. On this basis, further material libraries are produced. Using their globally unique high-throughput methods, the Erlangen researchers investigate the electrochemical performance of these libraries. The focus is on the split-second, simultaneous detection of both activity and stability as well as selectivity of the catalyst materials, which enables rapid and comprehensive analysis under different operating conditions. The Bern team then uses the best combinations of materials to produce catalysts in the form of nanoparticles that could be translated into applications.
