Synergistic Cobalt and Ytterbium Co‐Doping Enables Robust and Active IrRuO x for Acidic Oxygen Evolution Reaction

ABSTRACT Balancing low iridium dosage and robust anodic stability remains a critical hurdle for practical proton exchange membrane water electrolysis (PEMWE). Although IrRuO x offers a cost‐effective alternative, current systems still suffer from the dual dilemma of excessive noble‐metal reliance and inadequate long‐term durability. Herein, we developed a cobalt and ytterbium co‐doped IrRuO x electrocatalyst (IrRuCoYbO x ) via a high‐temperature thermal shock (HTS)‐assisted strategy. The Co and Yb dual‐doping not only induces favorable lattice defects but also optimizes the electronic structure of the Ir/Ru sites. Benefiting from these modulations, the IrRuCoYbO x exhibits exceptional acidic oxygen evolution reaction (OER) performance, requiring an ultralow overpotential of 171 mV at 10 mA cm −2 . Furthermore, a PEMWE cell‐integrating IrRuCoYbO x achieves an industrial current density of 1.0 A cm −2 at a low cell voltage of 1.68 V, sustaining continuous electrolysis for over 200 h. This work effectively overcomes the performance bottleneck of IrRu‐based catalysts, providing a highly promising strategy for designing efficient, low‐iridium anodes toward practical PEMWE applications.