Engineering S-scheme W₁₈O₄₉/ZnIn₂S₄ heterojunction by Co_xP nanoclusters for enhanced charge transfer capability and solar hydrogen evolution

Enhancement of the light-absorption response and utilization of the photogenerated carriers represent a robust strategy for the design of high-performance photocatalyst. In this work, grafting Co_xP nanoclusters onto S-scheme heterojunction of W₁₈O₄₉/ZnIn₂S₄ (WO/ZIS-Co_xP) with strong response to the ultraviolet–visible–near infrared ray (UV–vis–NIR) region has been achieved, which possesses efficient electron-transfer-channel, and boosts charge-separation and transport kinetics. The as-prepared WO/ZIS-Co_xP yields an impressive solar-driven hydrogen production rate of 45 mmol·g⁻¹·h⁻¹. The increased photocatalytic performance is attributed to the synergistic effect of the composite catalyst: (1) The local surface plasmon resonance-induced “hot electron” injection of W₁₈O₄₉ significantly increases the electron density; (2) the engineered S-scheme directional electron transfer promotes charge separation and enhances the reducing capability of photoexcited electrons; and (3) Co_xP as electron-trap site for accelerating surface proton reduction reaction. This work provides a platform to impart nonprecious co-catalyst for engineering S-scheme heterojunction, serving a class of efficient solar-driven photocatalyst towards hydrogen production.