PGM‐Free Catalysts for Oxygen Evolution Reaction for Proton Exchange Membrane Water Electrolyzers

ABSTRACT Proton exchange membrane water electrolyzer (PEMWE) holds a promise for large‐scale and highly efficient hydrogen production through electrocatalytic water splitting. Its widespread commercial adoption, however, is hindered by its reliance on expensive and scarce platinum group metals (PGMs) as the electrode catalyst materials. This is particularly the case at the PEMWE anode where the costly iridium is required to promote oxygen evolution reaction (OER). This article provides a brief review of the recent progresses and challenges in searching for PGM‐free OER catalysts as the low‐cost replacement of PGM catalysts, as well as our perspectives on future research directions from rational catalyst design to their potential industrial deployment.