Bridging the gap between basic research and application: a half-cell setup for high current density measurements of Ir-based oxygen evolution reaction catalysts on porous transport electrodes

Electrochemical benchmarking in three-electrode setups at a laboratory scale can greatly accelerate the development of catalysts for the oxygen evolution reaction in proton exchange membrane water electrolyzers. However, current systems such as the rotating disk electrode suffer from measurement artifacts, low current densities, and limited extrinsic validity. In this study, we introduce a novel three-electrode setup referred to as the PTE setup, specifically designed to investigate OER catalysts on realistic porous transport electrodes (PTEs) used in the anode side of water electrolyzers at high current densities. We evaluated the effectiveness of the PTE setup using self-supported iridium oxide (IrO x ) and Ir-Co catalysts produced via physical vapor deposition on a porous Ti porous transport layer (PTL) and pressed to a Nafion membrane. Our results demonstrate that the PTE setup is capable of measuring the activity and stability of self-supported catalysts creating conditions found in the anode cell compartment of a single-cell electrolyzer at current densities up to 2 A cm geo −2 . This setup represents a promising alternative to traditional benchmarking techniques, offering a practical and efficient approach for evaluating catalyst performance in relevant electrochemical environments. Innovative PTE setup enhances laboratory benchmarking of next-generation catalysts for the oxygen evolution reaction under technologically relevant conditions.