Regulating the d-band center of tungsten‑molybdenum bimetallic alloys via incomplete carbon coating for enhanced proton dissociation and the photocatalytic hydrogen evolution of transition metal sulfides.

The directional migration of photogenerated electrons to highly active hydrogen evolution sites, synergistically combined with the precise regulation of hydrogen evolution reaction (HER) kinetics through optimal proton adsorption modulation, is a critical strategy for enhancing photocatalytic HER efficiency. In this work, we developed a WMo/C catalyst with simultaneously improved electrical conductivity and a precisely tuned d-band center by alloying metallic tungsten (W) with molybdenum (Mo) and partial carbon (C) encapsulation. This rational design achieved near‑platinum (Pt) HER performance while maintaining W's intrinsically low work function, thereby endowing the W₇Mo₁/C-modified ZnCdS (ZCS) heterojunction with superior surface HER kinetics and a reduced electron transfer energy barrier compared toPt-ZCS counterpart. The noble-metal-free WMo/C-ZCS composite demonstrated exceptional photocatalytic HER activity (33.27 mmol·g·h) under visible light irradiation, representing a 15.37-fold enhancement over pristine ZCS and a 1.73-fold improvement over optimized Pt-ZCS. Notably, the optimized catalyst exhibited an outstanding apparent quantum efficiency of 21.3% at 420 ± 20 nm. This study establishes a systematic design paradigm for concurrently engineering efficient directional electron transport pathways and catalytically active surfaces with significantly enhanced photocatalytic performance and exceptional stability.