Visible-light-driven hydrogen evolution over CdS/CuWO4 S-Scheme heterojunctions: Dual synergistic enhancement via interfacial charge transfer and photothermal activation

S-scheme heterojunctions can offer an effective strategy for spatially separating photogenerated charge carriers, thereby sig F nificantly enhancing photocatalytic performance. In this study, cadmium sulfide (CdS)/copper tungstate (C F uWO 4 ) (CdS/CW) S-scheme heterojunction photocatalysts with adjustable components were fabricated by decorating CdS nanorods with CuWO 4 nanoparticles. The optimal hydrogen evolution rate (2725.91 μmol g –1 h –1 ) of CdS/CW-10% with excellent cycling stability under visible light is 10.1-fold higher than pure CdS. Density functional theory calculations and photoelectrochemical analyses confirmed that the S-scheme charge-transfer mechanism from CdS to CuWO 4 is responsible for the enhanced photocatalytic performance by promoting charge separation. Additionally, the photothermal effect of CuWO 4 increased the local temperature of the photocatalyst, further accelerating the reaction kinetics. This study highlights a dual-enhancement approach based on interfacial charge modulation by constructing an S-scheme heterojunction and photothermal activation, providing valuable insights into the design of high-efficiency S-scheme photocatalysts for solar-driven hydrogen production.