Dual active site and metal-substrate interface effect endow platinum-ruthenium/molybdenum carbide efficient pH-universal hydrogen evolution reaction.

Exploring suitable dual active site and metal-substrate interface effect is essential for designing efficient and robust electrocatalysts across a wide pH range for the hydrogen evolution reaction (HER). Herein, alloyed platinum-ruthenium clusters supported on nanosheet-assembled molybdenum carbide microflowers (PtRu/MoC) are reported as efficient pH-universal electrocatalysts for HER. Due to dual active site and metal-substrate interface effect, the optimized PtRu/MoC electrocatalyst exhibits extremely low overpotentials (η) of 9, 19, and 33 mV to deliver 10 mA cm in 0.5 M HSO, 1.0 M KOH, and 1.0 M phosphate buffered electrolytes (PBS), outperforming the benchmark Pt electrocatalyst. In addition, PtRu/MoC achieves excellent stability of 200 h at a big current density of 500 mA cm in the anionic exchange membrane water electrolyzer. Density functional theory (DFT) calculations and in situ Raman spectra reveal that the interaction of PtRu clusters with MoC substrate, while Ru modulates the electron cloud density of Pt, thus accelerating HO dissociation and H* desorption on the surface of PtRu/MoC and thus synergistically enhancing the HER kinetics. The research opens up an efficient strategy to exploit cost-effective, high-performance, and pH-universal HER electrocatalyst while facilitating green hydrogen energy development.