Oxygen-deficient tungsten oxide inducing electron and proton transfer: Activating ruthenium sites for hydrogen evolution in wide pH and alkaline seawater.

In this work, Ru/WO 3 -O V was obtained through a simple hydrothermal method and low-temperature annealing. The interaction between metal and support induces the directed movement of electrons and protons, optimizing the hydrogen evolution activity of Ru sites. The prepared samples exhibit ultra-high hydrogen evolution activity in the whole pH range and alkaline seawater. [Display omitted] • Ru/WO 3 -O V exhibits ultra-high HER activity across the entire pH range. • Electron/proton transfer boosts Ru site efficiency via WO 3 -O V. • Outstanding alkaline seawater HER activity and practical application potential. The design of electrocatalysts for the hydrogen evolution reaction (HER) that perform effectively across a broad pH spectrum is paramount. The efficiency of hydrogen evolution at ruthenium (Ru) active sites, often hindered by the kinetics of water dissociation in alkaline or neutral conditions, requires further enhancement. Metal oxides, due to superior electron dynamics facilitated by oxygen vacancies (O VS) and shifts in the Fermi level, surpass carbon-based materials. In particular, tungsten oxide (WO 3) promotes the directed migration of electrons and protons which significantly activates the Ru sites. Ru/WO 3 -O V is prepared through a simple hydrothermal and low-temperature annealing process. The prepared catalyst achieves 10 mA cm−2 at overpotentials of 23 mV (1 M KOH), 36 mV (0.5 M H 2 SO 4), 62 mV (1 M PBS), and 38 mV (1 M KOH + seawater). At an overpotential corresponding to 10 mA cm−2 in 1 M KOH and 1 M KOH + seawater, the mass activity of Ru/WO 3 -O V is about 7.7 and 7.86 times that of 20 wt% Pt/C. The improvement in activity and stability arises from electronic modifications attributed to metal-support interaction. This work offers novel insights for modulating the HER activity of Ru sites across a wide pH range. [ABSTRACT FROM AUTHOR]