Ru nanoparticles supported on partially reduced TiO2 as highly efficient catalyst for hydrogen evolution

Highlights: • Reduced TiO₂-supported Ru nanocatalyst with negatively charged Ru and oxygen vacancies was prepared. • Ru/r-TiO₂ exhibited a superior hydrogen evolution activity in alkaline media. • Only an overpotential of 15 mV is need to deliver a benchmark current density of 10 mA cm⁻². • High HER activity was attributed to the synergy of promoting water dissociation and weakening OH* adsorption. The development of low-cost yet highly efficient catalysts for hydrogen evolution reaction (HER) is crucial for large-scale clean and sustainable hydrogen production from water splitting. Tuning the interfacial structure of catalyst has emerged as an effective strategy to optimize the intrinsic catalytic activity. In this study, we demonstrated the deposition of Ru nanoparticles by freshly prepared strong reductive Ti(III) oxide, resulting in Ru/reduced TiO₂ interface with oxygen vacancies. The as-prepared Ru/r-TiO₂ exhibited a superior HER performance over commercial Pt/C in alkaline media, with only a small overpotential of 15 mV required to deliver the benchmark current density of 10 mA cm⁻² and a high turnover frequency of 8.74 s⁻¹ achieved at an overpotential of 100 mV. Density functional theory calculation indicates that high electrocatalytic activity of Ru/r-TiO₂ is originated from the promotion of water dissociation and weakening OH adsorption by reduced TiO₂, which facilitate the conversion of water to H₂. This work provides an efficient strategy for the design of high-performance HER catalysts.