Membrane Electrode Assembly Design to Stabilize PGM-Free Materials within the Catalyst Layer for Oxygen Evolution Reaction in Proton Exchange Membrane Water Electrolyzer

Iridium and other platinum group metal (PGM)-based materials seem to be the only choices for the anode catalyst for proton exchange membrane (PEM) water electrolyzers. The electrolyzer stack cost for green hydrogen production remains high due to the cost of these PGM materials. Significant efforts have been made to decrease the loading of iridium used in the PEMWE system or to substitute it with nonprecious alternatives, such as various transitional materials. This study explores membrane electrode assembly (MEA) design to stabilize PGM-free materials for operation in a modified PEM water electrolyzer along with tuning parameters to enhance the performance and durability of the system. With this modified architecture, the cell voltage reached 1.884 V at 1 A/cm² and sustained over 200 h of operation at 200 mA·cm^–2, which is the best result reported thus far for commercial Co₃O₄.