Abstract: Photocatalytic hydrogen evolution (PHE) is an effective method to alleviate environmental pollution and energy crises. However, a single catalyst is faced with rapid carrier recombination and insufficient active sites. Herein, we doped the Ni element on a hollow structured Z-scheme heterojunction of ZnIn₂S₄ (ZIS) and CdS through an in-situ method. The construction of the direct Z-scheme heterojunction interface induces a strong redox potential and enhances the separation efficiency of photogenerated carriers. The doping of Ni not only provides more active sites but also can generate new electron states for facilitated charge separation and enhanced light absorption. As a result, the optimized HCdS@Ni-ZIS (HZN) showed excellent PHE (20.43 mmol g^-1 h^-1) and oxidative coupling of benzylamine (BA) with a conversion rate of 173.00 mmol g^-1 h^-1. Moreover, the excellent bifunctional photocatalytic performance is even better than some noble metal-based photocatalysts. This work presented here provides a facile approach for constructing efficient bifunctional catalysts for solar-driven energy conversion.

Key words: Photocatalysis, Hydrogen evolution, Hollow structure, ZnIn₂S₄ (ZIS), CdS