Membranes and Electrochemical Cells

We use unique tools to study the interaction of membrane constituents with radicals to improve our understanding of the chemical degradation of membranes, both proton exchange membranes (PEMs) and alkaline anion exchange membranes (AEMs), and develop novel antioxidant strategies. The image shows the 60Co gamma source at PSI, which is used for continuous water radiolysis studies. The ionizing radiation of the gamma-photons yields to water radiolysis and the formation of defined amounts of radicals, which then react with model compounds, representative of the membrane chemistry, dissolved in the aqueous solution. 

We synthesize and engineer new membranes and membrane additives for next generation H2 fuel cells and water electrolyzers. One focus topic is the use of non-fluorinated hydrocarbon membranes for fuel cells, where we collaborate with other world-renowned academic partners and aim to characterize the most-promising chemistries. In the area of water electrolyzers, we focus on currently established perfluorinated membranes and seek to engineer them for improved functionality in terms of conversion efficiency and durability. The image shows a transmission electron microscopy image of a cerium-zirconium oxide (CZO) supported Pt-nanoparticles, which are added to the membrane for the dual functionality of gas recombination (Pt) and radical scavenging (CZO). 

A key focus of the group is the in-situ characterization of membranes in single cells to understand performance characteristics and obtain durability metrics. The laboratory operates a number of commercial and in-house built testbenches for characterization of fuel cells, water and CO2 electrolyzers. The customized cell teststands allow us to adapt their functionalities to the particular research topics under investigation. We typically use custom-built single cell hardware. The image shows a fuel cell with an active area of 16 cm2 with a parallel flow field, which is suited for component degradation studies.