DFG Research Group "Multiscale Analysis of Complex Three-Phase Systems" (FOR 2397)

Gas diffusion electrodes (GDE) are used in various technically important electrochemical processes. These include the conversion of chemically stored energy into electrical energy, which takes place in fuel cells and metal-air batteries, as well as the reversal of these energy conversion processes in the form of electrochemical syntheses, such as chlor-alkali or CO2 electrolysis. In many of these technologies, however, GDE are the limiting components and therefore the main cost drivers.

In order to further improve the performance of GDE, an overall understanding of the complex interaction of reaction and transport processes in the electrodes is required. To investigate these processes in detail, the DFG research group FOR 2397 brings together sub-projects from seven research institutions across Germany.

In the working group at the ICVT, gas diffusion electrodes (GDE) based on silver powders are produced and characterized using various methods. This includes physical-chemical analyses of the pore system on the one hand and electrochemical characterization using half-cell measurements on the other. Based on these measurements, the aim is to quantitatively understand how process conditions and electrode properties affect the overvoltage of oxygen and_{CO2 reduction}. The results of all sub-projects will also be used to develop a mathematical model to describe the stationary overvoltage of GDE.