Efficient and Stable pH‐Universal Water Electrolysis Catalyzed by N‐Doped Hollow Carbon Confined RuIrOx Nanocrystals

Abstract A facile strategy is developed to fabricate 3 nm RuIrO x nanocrystals anchored onto N‐doped hollow carbon for highly efficient and pH‐universal overall water splitting and alkaline seawater electrolysis. The designed catalyst exhibits much lower overpotential and superior stability than most previously reported Ru‐ and Ir‐based electrocatalysts for hydrogen/oxygen evolution reactions. It also manifests excellent overall water splitting activities and maintains ≈100% Faradic efficiency with a cell voltage of 1.53, 1.51, and 1.54 V at 10 mA cm −2 for 140, 255, and 200 h in acid, alkaline, and alkaline seawater electrolytes, respectively. The excellent electrocatalytic performance can be attributed to solid bonding between RuIrO x and the hollow carbon skeleton, and effective electronic coupling between Ru and Ir, thus inducing its remarkable electrocatalytic activities and long‐lasting stability.