Experimental investigation of OER catalysts under real-life conditions in half-cell setup for Anion Exchange Membrane Water Electrolysis

Abstract

Anion exchange membrane water electrolysis (AEMWE) is an emerging technology combining the applicability of non-noble catalyst materials from traditional alkaline water electrolysis (AWE) with the low overpotentials and the compact design of proton exchange membrane water electrolysis (PEMWE). In the present work, different non-noble oxygen evolution reaction (OER) catalysts were studied and compared to the baseline reference catalyst

at 25 °Celsius and 60 °Celsius, conditions usually applied in kinetic investigation (RDE setup) and in industrial scale electrolyzers, respectively. The catalysts were used as membrane electrode assembly (MEA) in a half-cell with flowing electrolyte at current densities of up to 1000 mA cm⁻². The catalyst loading of the best performing

catalyst was varied while the influence of the PTL type on the electrode performance was also investigated with this catalyst. It could be shown that an optimal catalyst loading reduced the overpotentials and that a lower porosity of PTL, which can enhance the interfacial contact between catalyst layer and PTL, also significantly improves the performance of the catalyst. Overall, this work shows a way towards further improvements of catalyst-coated PTLs for AEMWE.