Modulating *OOH Adsorption on RuO2 for Efficient and Durable Acidic Water Oxidation Electrocatalysis

Acidic water electrolysis is of considerable interest due to its higher current density operation and energy conversion efficiency, but its real industrial application is highly limited by the shortage of efficient, stable, and cost-effective acidic oxygen evolution reaction (OER) electrocatalysts. Here, an electrocatalyst consisting of Ni-implanted RuO₂ supported is reported on α-MnO₂ (MnO₂/RuO₂-Ni) that shows high activity and remarkable durability in acidic OER. Precisely, the MnO₂/RuO₂-Ni catalyst shows an overpotential of 198 mV at a current density of 10 mA cm^-2 and can operate continuously and stably for 400 h (j = 10 mA cm^-2) without any obvious attenuation of activity, making it one of the best-performing acid-stable OER catalysts. Experimental results, in conjunction with density functional theory calculations, demonstrate that the interface electron transfer effect from RuO₂ to MnO₂, further enhanced by Ni incorporation, effectively modulates the adsorption of OOH^* and significantly reduces the overpotential, thereby enhancing catalytic activity and durability.