Efficient CdS Nanoparticle/Zn(OH)F Heterojunction Catalysts for Hydrogen Evolution

Photocatalytic water splitting H2 production based on semiconductor nanoparticle heterojunctions is an attractive strategy. Various morphologies of Zn(OH)F have been widely used in photocatalytic degradation of organic matter; however, its application in photocatalytic hydrogen production has been rarely reported. Herein, two kinds of morphologies catalysts, one rodlike CdS/Zn(OH)F (CdS/RZF) and the second flower-like heterojunction CdS nanoparticle/Zn(OH)F (CdS NP/FZF), were prepared by the simple and mild hydrothermal method. Interestingly, CdS NP/FZF exhibited superior photocatalytic activity to CdS/RZF due to the flower-like structure of Zn(OH)F, which prevented the aggregation of CdS nanoparticles, thereby exposing more active sites. Notably, the light absorption ability of CdS nanoparticle/NixZn1–x(OH)F (CdS NP/NZF) was greatly improved, which was due to the introduction of Ni2+. As a result, the H2 production rate of CdS NP/NZF (2410 μmol·g–1·h–1) was increased by 2.19 times compared to that of CdS NP/FZF. This remarkable enhancement of photocatalytic H2-evolution activity of CdS NP/NZF was attributed to its special morphology in addition to Ni2+ doping, which promoted the separation of photogenerated electrons and holes, as well as improved the ability of visible-light response. This work provides a family of catalysts as a promising candidate for photocatalytic hydrogen evolution.