Cu-Doped ZnIn₂S₄/Ni_xP Composites with Enhanced Carrier Dynamics and Photocatalytic Hydrogen Production Performance

Photocatalytic technology still faces enormous challenges to design and synthesize highly efficient photocatalytic materials with a high electron/hole separation efficiency, rapid charge migration, low carrier recombination rate, and strong visible light-harvesting capability. Herein, Cu-doped ZnIn 2 S 4 /Ni x P (marked Cu y ZIS/NP) composites were successfully synthesized by a simple two-step method. The synergistic effect of Cu 2+ doping and the Ni x P cocatalyst on hydrogen evolution performance was investigated in detail. The results showed that superior photoactivity over Cu y ZIS/NP composites was achieved. The optimal Cu 0.5 ZIS/NP-1/2 sample had a hydrogen evolution rate of 4746.3 μmol·g –1 ·h –1 under visible light irradiation, which was approximately 15.98 times higher than that of pure ZnIn 2 S 4 (297 μmol·g –1 ·h –1 ). This work may offer a valuable insight into understanding the synergistic effect of doping and cocatalysis and provide a guideline for designing and developing highly efficient visible light-driven photocatalysts toward a water splitting system.