Facile and Efficient Synthesis of Dual-Defect NiFe Layered Double Hydroxides for Enhanced Oxygen Evolution Reaction

In electrocatalysis, traditional single-atom catalysts (SACs) face challenges in achieving coordinated control of reaction pathways due to limitations such as single local energy levels and carrier recombination. By introducing an additional defect structure, it is possible to break the electronic structure symmetry, thereby activating SACs and potentially enhancing catalytic performance through synergistic effects. Herein, a straightforward one-step method is introduced to regulate oxygen vacancies (Ov) while simultaneously integrating atomically dispersed Ru onto nickel-iron layered double hydroxides (Ru1/NiFe-LDH_Ov) for catalyzing oxygen evolution reaction (OER). Notably, by incorporating Ru atoms and adjusting the water-to-methanol molar ratio, both the Ov concentration and catalyst structure can be effectively regulated. Theoretical simulations demonstrate that the synergistic interplay between Ov and Ru atoms induces a targeted modulation of the electronic configuration at catalytically active sites, significantly enhancing OER kinetics through tuning M–O covalency and weakening O–H binding. The optimized Ru1/NiFe-LDH_Ov catalyst exhibits superior OER activity with an overpotential of 253 mV at 10 mA cm⁻², a low Tafel slope of 43.1 mV dec⁻¹, and excellent long-term stability in 1.0 M KOH solutions. This dual-defect synergistic regulation strategy pioneers a new paradigm for high-efficiency catalyst design.