Fabrication of hierarchical flower-like BiOI/MoS2 heterostructures with highly enhanced visible-light photocatalytic activities

Abstract In the paper, a novel BiOI/MoS2 (BMS) heterojunction was prepared by a facile hydrothermal method. BiOI nanoplates grew in-situ on the surface of exfoliated MoS2 nanosheets, followed by anisotropic growth and self-assembly, forming a hierarchical flower-like heterostructure finally. Experimental results illustrated that MoS2 as well as the BiOI amounts play a vital role in influencing the morphology and photocatalytic activity of BMS heterojunctions. Among the obtained photocatalysts, BMS-8 displayed the strongest photocatalytic performance under visible light irradiation towards the degradation of rhodamine B (RhB) and disinfection of Pseudomonas aeruginosa (P. aeruginosa). The highly enhanced photocatalytic activity can be attributed to the synergistic effect and formation of a type II heterostructure between BiOI and MoS2, boosting the catalytic active sites, enhancing visible light harvesting, and promoting the efficient separation of photoinduced charge carriers. Moreover, BMS-8 composite showed a good stability in photocatalytic reaction, which favored a long-term use. The active species trapping experiments validated the dominating role of photogenerated holes (h+) and ⋅O2- radicals in the photocatalytic process for BMS-8 heterojunction. It is anticipated that this work can promote further interest in constructing novel heterostructures with controllable morphology and highly efficient photocatalytic activity for potential environmental purification and energy conversion.