Non-injection synthesis of L-shaped wurtzite Cu-Ga-Zn-S alloyed nanorods and their advantageous application in photocatalytic hydrogen evolution

Multinary copper-based chalcogenides have been exploited in photocatalytic hydrogen generation due to their exceptional visible light absorption properties and environmentally friendly character. Similar to other photocatalysts, to reinforce the charge separation and transfer is one of the most important pathways to enhance photocatalytic hydrogen evolution, which can be achieved by rationally designing the nanostructures and geometries of multinary copper-based chalcogenides. Herein, an improved photocatalytic hydrogen evolution is successfully realized in L-shaped Cu-Ga-Zn-S (CGZS) alloyed nanorods compared with the binary Cu31S16 and ternary CuGaS2 nanocrystals. The L-shaped wurtzite CGZS nanorods with a uniform spatial composition distribution are synthesized via a non-injection solution approach for the first time. The successive incorporation of zinc and gallium ions into Cu31S16 seeds leads to formation of Cu31S16-ZnS and Cu31S16-CGZS heteronanostructures and finally results in the formation of single phase CGZS nanorods. The intrinsic features of L-shaped wurtzite CGZS nanorods offer efficient spatial charge separation and electrical transport, which contribute synergistically to the improved photocatalytic activity. This study provides a new way to develop novel multinary copper-based chalcogenides with flexible nanostructures for efficient photocatalytic hydrogen production.