Interfacial synergistic effect of Ru nanoparticles embedded onto amorphous/crystalline WO3 nanorods on boosting the pH-universal hydrogen evolution reaction

The development of high-efficiency pH-universal electrocatalyst is of great significance for hydrogen evolution reaction (HER). In this work, a rod-like Ru/WO 3 -V O electrocatalyst was constructed for HER via a solid-phase reaction strategy. Due to the restriction of atomic migration at solid phase interface, plenty of oxygen vacancies (V O ) and structure distortions were generated in amorphous/crystalline WO 3 phase (WO 3 -V O ). The optimized Ru/WO 3 -V O annealed at 450 °C with 2.2  wt % Ru achieves outstanding intrinsic activity with low overpotential and Tafel slope in a 0–14 pH range. A turnover frequency value 7.2 higher than that of commercial Pt/C is abtaind on Ru/WO 3 -V O at overpotential of 100 mV. Density functional theory calculations reveal that H* adsorption and desorption balanced by tuning the interface electronic structure contributes synergistic effect to the pH-universal HER activity of Ru/WO 3 -V O . The crystalline/amorphous semiconductor-metal heterointerface is crucial to designing and synthesizing electrocatalysts for optimal HER activity.