Cu2MoS4/CdS Nanosheet-Modified Nanowire Nanocomposites for Significantly Improved Visible Light-Driven Photocatalytic H2 Evolution Activity

The development of photocatalysts with high charge separation efficiency and visible-light-harvesting capacity is still a great challenge. In this work, we report a simple hydrothermal treatment to decorate the CdS nanowires (NWs) with co-catalyst Cu2MoS4 nanosheets (NSs) for photocatalytic H2 evolution reaction (HER). Especially when the molar ratio of Cu2MoS4 to CdS is 3%, the Cu2MoS4/CdS shows excellent visible light-driven H2 evolution activity (1967.83 μmol g–1 h–1), which is 18.8 times higher than that of pure CdS. Structural characterizations demonstrate a well-designed structure of the Cu2MoS4/CdS, in which Cu2MoS4 NSs are tightly attached onto the CdS NWs to form a heterojunction. The optical property reveals that the 3%-Cu2MoS4/CdS nanocomposite displayed distinguished visible-light absorption capacity. Combined with the data analysis of the photoluminescence spectra, photocurrents, and electrochemical impedance spectra, it can be proved that there is effective separation of photogenerated electron–hole pairs in 3%-Cu2MoS4/CdS nanocomposite. All these factors synergistically boost the photocatalytic H2 evolution performance of the Cu2MoS4/CdS, providing a new concept for the rational design of highly efficient visible-light-driven sulfide photocatalysts.