Establishing library of structural changes of redox processes to understand oxygen evolution on IrOx catalysts

Iridium-based electrocatalysts are the most stable for the oxygen evolution reaction (OER) in proton-exchange membrane water electrolyzers (PEMWEs), but the link between activity and stability is unclear. While various types of IrOx catalysts (rutile, amorphous, hydrous) are used in PEMWEs, the specific reaction pathway depends on the structure to such an extent that the results for one structure type are challenging to transfer and generalize. In this work, we will build a library of structural changes during redox mechanisms in rutile IrO2 nanoparticles and amorphous IrOx on metallic Ir. Using XRD-CV, we correlate oxidation/reduction with changes in scattering intensity and lattice parameters. By varying potential limits, we aim to find optimal voltage control for a prolonged PEMWE lifespan. This study provides fundamental insights into Ir-based OER catalysts, informing strategies to improve PEMWE durability and economic viability.