Recent Developments in Single‐Atom Engineering Ir/Ru‐Based Catalysts for the Oxygen Evolution Reaction in Acidic Media

Abstract Proton exchange membrane water electrolysis (PEMWE) is a critical technology for sustainable green hydrogen production, yet its efficiency and cost are severely constrained by the kinetically sluggish kinetics and material instability of the anodic oxygen evolution reaction (OER) in acidic media. Iridium (Ir)‐ and ruthenium (Ru)‐based oxides remain the benchmark catalysts for this demanding reaction, but still face significant challenges such as the high cost and inadequate activity of Ir and the poor stability of Ru under harsh anodic conditions. In this review, recent breakthroughs in overcoming these limitations are comprehensively summarized through the strategic engineering of Ir‐ and Ru‐based electrocatalysts via single‐atom doping (SAD). Controllable synthetic methods for SAD Ir/Ru‐based catalyst design are summarized, and their underlying reaction mechanisms in the acidic OER are discussed. This single‐atom engineering method, as a promising strategy, shows exceptional potential and reliability for developing high‐performance and durable Ir/Ru‐based acidic OER catalysts, paving the way for more efficient and economically viable PEMWE systems.