A visible-light driven Bi₂S₃@ZIF-8 core–shell heterostructure and synergistic photocatalysis mechanism

Abstract

Visible-light-driven organic transformations have received much attention because of their low cost, relative safety, and environmental friendliness. In this work, we report a series of Bi₂S₃@ZIF-8 core-shell heterostructures prepared using a simple and efficient self-assembly process. The photocatalytic activity was evaluated using the photocatalytic degradation of Rhodamine B (RhB) under visible-light irradiation and the results show that the core-shell Bi₂S₃@ZIF-8 heterostructure can remarkably enhance the photocatalytic efficiency at room temperature compared to pristine Bi₂S₃ nanorods. In addition, the Bi₂S₃@ZIF-8 composite with a Bi/Zn molar ratio of 1/10 demonstrates good structural stability after the degradation experiment and its photocatalytic activity remains at about 95% after the five recycling tests. The improved photocatalytic performance can be attributed to the larger specific surface area, increased light absorption, and more efficient separation of photogenerated electron-hole pairs due to the combined effects of Bi₂S₃ and ZIF-8. Moreover, the synergistic photocatalysis mechanism was investigated.