Simultaneous realization of sulfur-rich surface and amorphous nanocluster of NiS1+x cocatalyst for efficient photocatalytic H2 evolution

Transition-metal sulfides have been proved to be a favorable candidate for high-efficiency cocatalyst for photocatalysts, but the major bottlenecks remains lacking sufficient active sites for interfacial H-2-generation reactions. In this article, the sulfur-rich NiS1+x nanoclusters with abundant active unsaturated S sites are homogeneously anchored on TiO2 particles by a facile S2O32--mediated photodeposition route. The as-synthesized NiS1+x/TiO2(1 wt%) photocatalyst achieves the boosted H-2 evolution rate of 264.42 mu mol h(-1) as well as shows an outstanding stability and repeatability. The sulfur-rich NiS1+x nanoclusters can not only act as an outstanding cocatalyst to effectively accelerate the electron migration from TiO2 to NiS1+x nanoclusters, but also provide numerous active unsaturated S sites to promote interfacial H-2-generation reaction, thereby promoting the photocatalytic H-2 -production rate of the NiS1+x/TiO2 photocatalysts. Particularly, the present method can be extended to construct other metal sulfides (AgSx, CoSx or CuSx) to evidently promote the photocatalytic H-2-evolution activity.

Automated summary

Transition-metal sulfides, such as NiS1+x nanoclusters, have been shown to enhance H-2 evolution rates in photocatalysts by providing active unsaturated S sites. The study demonstrates that NiS1+x nanoclusters anchored on TiO2 particles greatly improve the efficiency and stability of photocatalytic H-2 production. This method can also be extended to other metal sulfides to further enhance H-2-evolution activity.