Harnessing Synergistic d-p Band Center Modulation of RuO2 nanofibers via Dual-Site Doping for Highly Active and Stable Water Electrolysis

Addressing the inherent activity and stability limitations of RuO 2 catalyst in water electrolysis, this study introduces a targeted electronic structure modulation approach through the simultaneous incorporation of functionally complementary Mo (cation) and S (anion) heteroatoms. This dual-site synergistic doping strategy precisely regulates both the Ru d -band center and the O p -band center within RuO 2 , optimizing the coupling strength and energetic alignment of the d-p orbitals. Therefore, the Mo, S-doped RuO 2 nanofibers (NFs) balance the adsorption/desorption energetics of intermediates and accelerates reaction kinetics. This new structure also benefits to enhance the durability. Consequently, the resulting Mo, S-doped RuO 2 NFs deliver superior bifunctional water splitting performance, requiring only 221.0 mV overpotential for oxygen evolution reaction at 10 mA cm −2 and maintaining the performance up to 200 h at 1 A cm −2 , while achieving hydrogen evolution reaction to feature mere 187.7 mV overpotential at 1 A cm −2 and 200 h stability at this current density. This work unlocks a new pathway to promote the electrocatalytic performance of Ru-based catalysts via d-p band center engineering under industrial-level water electrolysis conditions.