In July 2016, Deutsche Forschungsgemeinschaft (DFG) approved the Research Group 2397 under the leadership of Clausthal University of Technology. The research project "Multi-scale analysis of complex three-phase systems" is devoted to a better understanding of the complex processes within gas-diffusion electrodes (GDE). GDE are functional materials that are used in various technically important electrochemical processes such as fuel cells, electrolyzers, and metal-air batteries. The development and manufacture of these materials is of particular importance in view of the challenges of the energy transition. The aim of the Research Unit is to understand and quantitatively describe the complex interaction of reaction and transport processes in GDE and their influence on the performance of the electrodes.

In the first project phase (2016 – 2019), the main research focus was on the investigation of the kinetics of the oxygen reduction reaction (ORR) on silver surfaces and on the detection and simulation of the penetration of a liquid electrolyte into the pore system consisting of hydrophilic and hydrophobic components. In addition, the relationships between the porous structure of the GDE, the process conditions and the essential electrode properties were determined.

In the second project phase (2020 – 2022), the important effect of electrowetting phenomena on the distribution and transport of the electrolyte in the pore system of the GDE will be investigated with novel experiments and through mathematical simulations. Moreover, the findings obtained during the investigation of the ORR will be transferred to the carbon dioxide reduction reaction (CO2RR), which selectively produces carbon monoxide over Ag-GDE.

Overall, this deeper understanding is achieved through the targeted collaboration of various working groups from the fields of material characterization, tomography, electrochemistry and chemical process engineering. Scientists from a total of seven universities and research institutions are participating in the project across Germany.