<p>The rational design and optimization of noble-metal-free semiconductor photocatalysts aim to increase the number of active sites and accelerate the separation and transfer of charges, thereby achieving high-performance hydrogen evolution reactions (HER). In this study, we innovatively designed an S-scheme heterojunction catalyst composed of CdS nanoparticles rich in cationic Cd vacancies (V_CCS) and ZnWO₄ nanorods rich in anionic O vacancies (V_OZWO) that regulate the surface electronic states of the catalyst through dual vacancies engineering. Specifically, the introduction of vacancy engineering effectively adjusted the energy level structure of the catalyst, achieving bandgap narrowing, enhancing light absorption capacity, providing hole trapping sites, and creating more active sites. As expected, the optimized V_OZWO@V_CCS heterojunction exhibited exceptional photocatalytic H₂ production rates of 11.55 mmol g⁻¹ h⁻¹ in the absence of noble-metal cocatalysts, which are approximately 462 times and 4 times higher than those of pure V_OZWO (0.025 mmol g⁻¹ h⁻¹) and V_CCS (2.89 mmol g⁻¹ h⁻¹), respectively. In-depth characterization tests and density functional theory (DFT) calculations revealed that the introduction of vacancies significantly reduced the bandgap, improved the transfer efficiency of photoinduced carriers, and validated the charge transfer mechanism of the S-scheme heterojunction.</p>