Electron redistribution of ruthenium-tungsten oxides Mott-Schottky heterojunction for enhanced hydrogen evolution

Developing efficient electrocatalysts is of significance for hydrogen production in acid electrolyte. In this work, we report a facile decoration of ruthenium species onto tungsten oxides to construct the Mott-Schottky heterojunction electrocatalyst for hydrogen evolution. The resultant Ru-WO2.72 hybrid exhibits a superior Ru-based mass activity of 161.6 times higher than that of commercial Ru/C for hydrogen evolution, featuring a Tafel slope of 50 mV dec−1 and 40 mV overpotential at the current density of 10 mA cm−2. The uniform distribution of Ru species triggers a strong electron transfer across the Ru-WO2.72 Schottky barrier, resulting in a largely increased local electron density on the active Ru surface. Such electron enrichment induced by the Mott-Schottky effect at the metal-metal oxides interface is responsible for enhanced hydrogen production. This work demonstrates an effective strategy by Mott-Schottky effect to regulate electron distribution, which would evoke more inspiration in designing efficient electrocatalysis and beyond. The interface coupling between WO2.72 and Ru in Ru-WO2.72 Mott-Schottky would be responsible for the excellent electrocatalytic hydrogen evolution in acidic electrolyte. [Display omitted] •A Ru-WO2.72 M-S heterojunction is constructed by a facile method.•The Ru-WO2.72 hybrid exhibits a superior activity for HER.•Electron enrichment induced by the M-S effect is responsible for the enhanced HER.