Recent Advances in Ir-based Electrocatalysts for Oxygen Evolution in Acidic Media: A Mini-Review

Acidic proton exchange membrane water electrolyzer (PEMWE) offers high current density operation, rapid dynamic response and compact architecture, making it highly attractive for large-scale hydrogen production.To sustain such demanding conditions, anode electrode must combine high catalytic activity with long operational durability.Iridium (Ir) oxides remain the state-of-the-art choice due to their unique stability in strong acid.However, the scarcity of Ir and the limited intrinsic activity of Ir-based electrocatalysts present major obstacles for commercialization.Recent advances in Ir-based electrocatalysts highlight how rational design strategies can enhance performance while reducing Ir loading.Strategies include tuning electronic structure through metal doping, controlling morphology to increase active sites, and using supports for uniform dispersion, Ir stabilization, and efficient charge transport.Amorphous and metastable phases have also emerged as promising frameworks.Their disordered structures create abundant active sites and enable adaptive reconstruction pathways that enhance activity.In parallel, mechanistic studies continue to refine our understanding of oxygen evolution on Ir oxides, revealing the interplay of multiple pathways.This mini-review consolidates progress across mechanistic insights, materials innovations, and device-level evaluations.With coordinated advances, Ir-based electrocatalysts are moving closer to enabling commercially viable PEMWE for sustainable hydrogen production.