One-pot Synthesis of CdS Irregular Nanospheres Hybridized with Oxygen-Incorporated Defect-Rich MoS2 Ultrathin Nanosheets for Efficient Photocatalytic Hydrogen Evolution

Robust and highly active photocatalysts, Cds@MoS2, for hydrogen evolution were successfully fabricated by one-step growth of oxygen-incorporated defect-rich MoS2 ultrathin nanosheets on the surfaces of CdS with irregular fissures. Under optimized experimental conditions, the CdS@MoS2 displayed a quantum yield of similar to 24.2% at 420 nm and the maximum H-2 generation rate of similar to 17203.7 umol/g/h using Na2S-Na2SO3 as sacrificial agents (lambda >= 420 nm), which is similar to 47.3 and 14.7 times higher than CdS (similar to 363.8 mu mol/g/h) and 3 wt % Pt/CdS (similar to 1173.2 mu mol/g/h), respectively, and far exceeds all previous hydrogen evolution reaction photo catalysts with MoS2 as co-catalysts using Na2S-Na2SO3 as sacrificial agents. Large volumes of hydrogen bubbles were generated within only 2 s as the photocatalysis started, as demonstrated by the photocatalytic video. The high hydrogen evolution activity is attributed, to several merits: (1) the intimate heterojunctions formed between the MoS2 and CdS can effectively enhance the charge transfer ability and retard the recombination of electron-hole pairs; and (2) the defects in the MoS2 provide additional active S atoms on the exposed edge sites, and the incorporation of O reduces the energy barrier for H-2 evolution and increases the electric conductivity of the MoS2. Considering its low cost and high efficiency, this highly efficient hybrid photocatalysts would have great potential in energy-generation and environment-restoration fields.