Synergistic Ruthenium-Doped Amorphous IrOx Matrix for Robust Oxygen Evolution

Iridium oxides (IrOx) are benchmark catalysts for the acidic oxygen evolution reaction, but their performance is often constrained by a trade-off between catalytic activity and long-term stability. Herein, we utilize an amorphous IrOx matrix as a robust scaffold for synergistic ruthenium (Ru) doping, a strategy designed to enhance catalytic activity while maintaining an exceptional stability. A simple nitrate-assisted synthesis produces ultrathin Ru-doped amorphous IrOx nanosheets (2.36 nm thick) with a significantly enhanced specific surface area. Combined spectroscopic analysis and density functional theory calculations reveal that atomically dispersed Ru dopants induce charge transfer to adjacent Ir sites, which optimizes the Ir d-band electronic structure. This electronic modulation not only lowers the energy barrier for the rate-determining *O to *OOH transformation but also critically ensures the reaction proceeds via the stable adsorbate evolution mechanism while suppressing the degradative lattice oxygen mechanism. Benefiting from the above advantages, the optimized Ru0.0738–IrOx catalyst exhibits excellent catalytic activity, achieving 10 mA cm–2 at a low overpotential of 225 mV with outstanding stability for over 100 h, far surpassing commercial IrO2 and RuO2. This study highlights a synergistic doping strategy within an amorphous matrix to overcome the intrinsic performance limitations of iridium-based oxides for robust oxygen evolution.