Chalcogen‐Bridge‐Regulated Proton Shuttling in Tantalum‐Doped Ruthenium Oxide for Robust Acidic Water Oxidation

ABSTRACT The acidic oxygen evolution reaction (OER) kinetics on ruthenium dioxide (RuO 2 ) is fundamentally restricted by sluggish deprotonation and interfacial proton transfer. Herein, we introduce chalcogen atoms to tantalum doped RuO 2 (Ta─X─RuO 2 , X = O, S, Se, and Te) and reveal its effects on proton shuttling, including deprotonation and proton transfer from electrocatalyst surface to bulk electrolyte. Significantly, Ta─S─RuO 2 exhibits optimized OER performance due to the balanced hydrogen binding strength of bridge sulfur atoms, promoting deprotonation kinetics and modulating the interfacial water structure to form flexible hydrogen bond network for accelerated proton transfer. Only 1.89 V is demanded for Ta─S─RuO 2 to reach 3 A cm −2 geo and maintains robust performance for 1000 h with voltage decay of 49.0 µV h −1 stemming from the efficient hydrogen bond network to lower the local H + concentration, suppressing the overoxidation of Ru. This work not only reports a novel high‐performance Ta─X─RuO 2 electrocatalysts for acidic OER but also provides new insight into chalcogen‐regulated proton shuttling and promoted OER kinetics and stability, offering guidance to the design of future generation RuO 2 ‐based electrocatalyst.