Data- and Theory-Guided Design of Dual-Role V-Doped RuO₂ for High-Performance Acidic Oxygen Evolution

Developing efficient acidic oxygen evolution reaction (OER) catalysts is crucial for proton exchange membrane water electrolyzers (PEMWE). By mining a dataset of 718 reported catalysts, we statistically identified that multi-metal Ru-based oxides significantly outperform monometallic counterparts (median overpotential: 210 vs. 283 mV). Guided by this insight, microkinetic modeling screened 20 metal dopants, pinpointing vanadium as a promising candidate. The synthesized V-doped RuO₂ (RV) exhibits an ultralow overpotential of 193 ± 1 mV at 10 mA cm^-2 and robust stability for 3000 h. In a practical PEMWE device, RV achieves an industrial current density of 1 A cm^-2 at only 1.725 V and sustains operation for 140 h at 200 mA cm^-2. Mechanistic studies reveal that V-doping plays a dual role in RuO₂. It induces Lewis acidic Ru sites to accelerate deprotonation kinetics, while simultaneously acting as a dynamic redox buffer to prevent Ru over-oxidation. This work shows how data- and theory-guided screening, combined with mechanistic investigation, can accelerate the discovery and understanding of high-performance RuO₂-based acidic OER catalysts.