Dr. Raül Garcia Diez received poster award at the international synchrotron conference SRI 2018
Raül Garcia Diez is awarded the poster prize. © SRI 2018
HZB researcher introduces unique operando characterization by soft X-ray spectroscopy
The HZB physicist Raül Garcia Diez has been awarded a poster prize at the international conference "Synchrotron Radiation Instrumentation 2018" (SRI 2018) in Taiwan. He presented how the HZB team intends to observe the reactions in electrocatalysts under "operando" conditions with soft X-rays from BESSY II.
“Operando" analysis is of vital importance for investigating catalytic processes in materials and getting insights into the chemical reaction. This enables researchers to understand the mechanisms that limit the performance and stability of electrocatalyst materials. However, "operando" characterization techniques for catalysts and liquid environments - especially for soft X-ray applications - have to been pushed beyond the current limits first.
"Operando" investigations in a wide energy range
Dr. Raül Garcia Diez is part of Dr.-Ing. Marcus Bär's young investigator research group, which is developing this experimental setup in the EMIL laboratory. This includes a compact X-ray spectrometer (HiTS: "High transmission soft x-ray emission spectrometer") and a flow-cell suited for electrochemistry. The X-ray optics designed for the HiTS spectrometer enable material investigations over an extremely wide energy range (from 50 to 2,000 eV).
"Our design sets new standards in the field of soft X-ray spectroscopy. I am happy that I could report at the conference about the progress made in developing the EMIL infrastructure for “operando” measurements. The poster award is a recognition of our work," says Raül Garcia Diez.
The International Conference on Synchrotron Radiation Instrumentation takes place every three years. With approximately 800 participants, it is the largest conference in this field; almost all synchrotron facilities in the world were represented at this year's conference with talks and posters.
- Battery research with the HZB X-ray microscopeNew cathode materials are being developed to further increase the capacity of lithium batteries. Multilayer lithium-rich transition metal oxides (LRTMOs) offer particularly high energy density. However, their capacity decreases with each charging cycle due to structural and chemical changes. Using X-ray methods at BESSY II, teams from several Chinese research institutions have now investigated these changes for the first time with highest precision: at the unique X-ray microscope, they were able to observe morphological and structural developments on the nanometre scale and also clarify chemical changes.
- BESSY II: New procedure for better thermoplasticsBio-based thermoplastics are produced from renewable organic materials and can be recycled after use. Their resilience can be improved by blending bio-based thermoplastics with other thermoplastics. However, the interface between the materials in these blends sometimes requires enhancement to achieve optimal properties. A team from the Eindhoven University of Technology in the Netherlands has now investigated at BESSY II how a new process enables thermoplastic blends with a high interfacial strength to be made from two base materials: Images taken at the new nano station of the IRIS beamline showed that nanocrystalline layers form during the process, which increase material performance.
- Hydrogen: Breakthrough in alkaline membrane electrolysersA team from the Technical University of Berlin, HZB, IMTEK (University of Freiburg) and Siemens Energy has developed a highly efficient alkaline membrane electrolyser that approaches the performance of established PEM electrolysers. What makes this achievement remarkable is the use of inexpensive nickel compounds for the anode catalyst, replacing costly and rare iridium. At BESSY II, the team was able to elucidate the catalytic processes in detail using operando measurements, and a theory team (USA, Singapore) provided a consistent molecular description. In Freiburg, prototype cells were built using a new coating process and tested in operation. The results have been published in the prestigious journal Nature Catalysis.