A novel hierarchical CdS-DETA@CoP composite as highly stable photocatalyst for efficient H2 evolution from water splitting under visible light irradiation

Abstract

The photolysis of water using photocatalysts under sunlight irradiation for hydrogen generation reaction is an efficient strategy to solve energy and environmental issues. Herein, a novel hierarchical CdS-DETA@CoP composite was fabricated and applied to visible-light-driven photocatalytic water splitting for generating H2. To achieve this goal, we first prepared a 3D hierarchical CoP co-catalyst via direct phosphatization of the ZIF-67 precursor. Then, two-dimensional (2D) CdS-DETA nanosheets were in situ grown on the surface of hierarchical CoP through a facile water bath method, obtaining a CdS-DETA@CoP composite with a high surface area. The CdS-DETA@CoP composite with 20 wt% CoP exhibits a maximum photocatalytic H2 evolution rate of 48.76 mmol g–1h−1 under visible light irradiation with lactic acid as the sacrificial reagent, which is 46.4 times as high as CdS-DETA. The synergistic effect between CdS-DETA and CoP induced remarkable ability of light-harvesting and efficient separation of photogenerated electron-hole pairs, thus profoundly promoting the activity and stability. The excellent activity is also closely related to the better dispersion of CdS-DETA on the surface of hierarchical CoP co-catalyst.