Mapping Proton Exchange Membrane Water Electrolyzer (PEMWE) with Ir/ZrOx and IrCeOx Anodic Catalyst via 2D XRF and XANES

Proton exchange membrane water electrolysis (PEMWE) is an emerging technology in conversion of renewable electricity to fuels (e.g., H2). Current benchmark catalysts rely on Pt-based cathode and Ir-based anode materials. The oxygen evolution reaction occurs at the anode under harsh conditions (high potential, low pH, high O2 concentration), so that catalysts must be highly tolerant and stable. Despite the cost and scarcity of noble metals, it has proven challenging to replace these with sustainable alternatives, so current research efforts aim at (i) improving stability (particularly of Ir-based anodes) and (ii) improving catalytic activity, allowing decreased Pt/Ir loading. Our recent lab studies indicate that supporting Ir on ZrOx and CeOx leads to improved catalyst stability over 100 h compared to benchmark materials. Here we aim to monitor and quantify electrode stability in terms of metal migration from the electrodes to the polymer membrane using 2D nano-XRF and XANES mapping.