Redistribution of local electronic structure in RuO2 via empty d-orbital yttrium doping for robust acidic water oxidation

The development of highly active and durable catalysts for the acidic oxygen evolution reaction (OER) is urgently needed to accelerate reaction kinetics and reduce energy barriers. Herein, we propose to tune the local electronic structure in RuO 2 via yttrium ion (Y 3+ ) doping to facilitate the OER process following oxide path mechanism (OPM). The electron-deficient of Y 3+ redistributes local charge density, strengthens metal–oxygen bonds to suppress lattice degradation. Moreover, the incorporation of larger Y 3+ radius reduce the Ru–Ru distance, and thereby benefits O–O coupling. The optimized Y 0.11 Ru 0.89 O 2−δ catalyst exhibits an exceptionally low overpotential of 195 mV at 10 mA cm −2 for acidic OER and operates stably for 250 h at 100 mA cm −2 in a PEM electrolyzer. Theoretical investigations reveal that Y–O–Ru structure effectively modifies the chemical environment and optimizes the atomic configuration of active sites. This study establishes electron-deficient, large-radius dopants as an effective strategy for designing efficient and durable acidic OER catalysts, enhancing RuO 2 performance.