Homologous heterostructure CdSe/CdS nanoflowers to enhance photocatalytic hydrogen production

The study of nano-heterostructures as light-capturing system applied in photocatalytic water splitting is a current research hotspot. In this study, a simple in situ anion exchange method was proposed for the synthesis of homologous heterostructure CdSe/CdS nanoflowers. Series of CdSe/CdS composites were obtained by controlling the amounts of Se powder. The optimum ratio 5 wt% CdSe loading on CdS nanosheets achieved the maximum H2 production rate of 16.03 mmol g-1 h-1, which was 1.5 times higher than that of pure CdS. Mechanism study with UV-vis DRS, and photoluminescence revealed the excellent photocatalytic property was attributed to the expansion the absorption range of CdS with the introduction of CdSe, the construction of the Z-scheme heterojunction between CdS and CdSe, and the rich catalytic reaction interfacial sites provided by the hierarchical structure with 2D nanosheets and 3D nanoflowers. This work provided the design and synthesis of homologous heterostructure photocatalysts for high efficiency hydrogen production.