Structurally‐Distorted RuIr‐Based Nanoframes for Long‐Duration Oxygen Evolution Catalysis

Abstract Oxygen evolution reaction (OER) plays a key role in proton exchange membrane water electrolysis (PEMWE), yet the electrocatalysts still suffer from the disadvantages of low activity and poor stability in acidic conditions. Here, a new class of CdRu 2 IrO x nanoframes with distorted structure for acidic OER is successfully fabricated. Impressively, CdRu 2 IrO x displays an ultralow overpotential of 189 mV and an ultralong stability of 1500 h at 10 mA cm⁻ 2 toward OER in 0.5 M H 2 SO 4 . Moreover, a PEMWE using the distorted CdRu 2 IrO x can be steadily operated at 0.1 A cm⁻ 2 for 90 h. Microstructural analyses and X‐ray absorption spectroscopy (XAS) demonstrate that the synergy between Ru and Ir in CdRu 2 IrO x induces the distortion of Ru−O, Ir−O, and Ru−M (M = Ru, Ir) bonds. In situ XAS indicates that the applied potential leads to the deformation octahedral structure of RuO x /IrO x and the formation of stable Ru 5+ species for OER. Theoretical calculations also reveal that the distorted structures can reduce the energy barrier of rate‐limiting step during OER. This work provides an efficient strategy for constructing structural distortion to achieve significant enhancement on the activity and stability of OER catalysts.