Transition metal-doped V-shaped RuO₂ 103 nanotwins as highly active electrocatalysts for enhanced oxygen evolution in acidic media

Abstract

Efficient and stable catalysts for the oxygen evolution reaction (OER) in acidic environments are essential for hydrogen production through electrolysis. The paper reported the transition metal-doped RuO2 103 nanotwins (RuO2 103-NTs), as cost-effective and high-performance catalysts for acidic OER. The MRu-VO defect models were constructed by introducing transition metal (Ag, Mn, Fe, Co, Cu, and Zn) doped surfaces. Thereinto, the AgRu-VO doped structure exhibited remarkable OER activity in acidic conditions, achieving a reduced overpotential of 0.37 eV. Furthermore, we investigated the synergistic effect of the Ag and oxygen vacancies (VO) in conjunction with grain boundaries. Above results revealed that an increase in the content of Ag and VO resulted in a decrease in structural stability, leading to a more disordered structure. By analyzing the adsorption energy, energy band center and charge transfer in bimetallic-doped NTs, we observed that the presence of MRu-AgRu-VO (M = Mn, Co, Fe) significantly promotes the positive shift of d band center and the increase of charge transfer. This effect ultimately led to a decrease in the overpotential of the rate-determining step to 0.27 eV, thereby enhancing the intrinsic activity of RuO2.