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-WO_2.72 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-WO_2.72 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.