Smart Hybridization of Au Coupled CdS Nanorods with Few Layered MoS₂ Nanosheets for High Performance Photocatalytic Hydrogen Evolution Reaction

Fabrication of core–shell heteronanostructures with excellent optical properties and light induced charge separation effects have recently emerged as promising materials for solar to hydrogen conversion. Here, one-dimensional CdS–Au/MoS 2 hierarchical core/shell heteronanostructures (CSHNSs) have been successfully synthesized by a facile two-step hydrothermal method. Such heteronanostructures exhibit high efficiency and excellent stability toward hydrogen production. The introduction of Au nanoparticles on to CdS nanorods not only made a Schottky junction with strong plasmonic absorption enhancement but also directed the growth of few layered MoS 2 nanosheets as a hierarchical protective shell around the CdS nanorods. These CdS–Au/MoS 2 hybrid structures possess a large number of edge sites in the MoS 2 layers which are active sites for hydrogen evolution reaction. As a result, the CdS–Au/MoS 2 CSHNSs exhibit outstanding hydrogen evolution performance which is 7 times that of pure CdS nanorods. Also these CdS–Au/MoS 2 CSHNSs showed greater stability after a long-time test (16 h), and 90% of catalytic activity still remained. The enhanced hydrogen evolution activity of CdS–Au/MoS 2 CSHNSs was attributed to the improved visible light absorption and the formation of heterojunctions between CdS, Au, and MoS 2 components, which increases the charge separation efficiency and thereby suppresses the electron–hole recombination.