Reduced graphene oxide as an efficient support for CdS-MoS2 heterostructures for enhanced photocatalytic H2 evolution

Cadmium sulphide nanorods-reduced graphene oxide-molybdenum sulphide(CdS-rGOMoS(2)) composites were successfully synthesized using hydrothermal process for enhancing the interfacial contact between CdS nanorods and MoS2 layer. The good contact between CdS and MoS2 is important for improving the photocatalytic hydrogen (H-2) evolution. The morphological and structural studies showed the production of highly pure CdS phase with nanorod-like structure dispersed on rGO-MoS2 layer. X-ray photoelectron spectroscopy (XPS) and Raman results confirmed the reduction of graphene oxide (GO) into reduced graphene oxide (rGO). The higher photocurrent density of CdS-rGO-MoS2 composites compared to CdS/MoS2 and the fluorescence quenching observed for this composite provided some evidence for an inhibition of electron-hole recombination, which leads to a longer life time of the photogenerated carriers. Fast electron transfer can occur from CdS nanorods by the bidimensionnel rGO area to MoS2 layer due to the intimate interfacial contact. Composite CdS-rGO-MoS2 with 20 wt% rGO was found to be the most effective photocatalyst for H-2 evolution (7.1 mmol h(-1)g(-1)). The good photocatalytic performance arose from the positive synergistic effect between CdS, rGO and MoS2 elements. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.