Breaking the Ru‐O‐Ru Symmetry of a RuO2 Catalyst for Sustainable Acidic Water Oxidation

Proton exchange membrane water electrolysis is a highly promising hydrogen production technique for sustainable energy supply, however, achieving a highly active and durable catalyst for acidic water oxidation still remains a formidable challenge. Herein, we propose a local microenvironment regulation strategy for precisely tuning In‐RuO2/graphene (In‐RuO2/G) catalyst with remarkably intrinsic electrochemical activity and stability to boost acidic water oxidation. The In‐RuO2/G displays robust acid oxygen evolution reaction performance with a mass activity of 671 A gcat−1 at 1.5 V, an overpotential of 187 mV at 10 mA cm−2, and long‐lasting stability of 350 h at 100 mA cm−2, which arises from the asymmetric Ru‐O‐In local structure interactions. Further, it is unraveled theoretically that the asymmetric Ru‐O‐In structure breaks the thermodynamic activity limit of the traditional adsorption evolution mechanism which significantly weakens the formation energy barrier of OOH*, thus inducing a new rate‐determining step of *OH absorption. Therefore, this strategy showcases the immense potential for constructing high‐performance acidic catalysts for water electrolyzers.