Fabrication of Bi4O5Br2-decorated rod-like MOF-derived MoS2 hierarchical heterostructures for boosting photocatalytic CO2 reduction

Bi-based semiconductors have been regarded to be an ideal platform in photocatalytic CO 2 reduction to fuels. However, the insufficient charge transfer efficiency greatly restricts their practical application. Herein, we fabricated 1D/2D hierarchical heterostructures by the hybridization of Bi 4 O 5 Br 2 and rod-like MOF-derived MoS 2 anchored in nitrogen-doped porous carbon (NPC-MoS 2 ) using Mo-MOF as a precursor followed by sulfidation and typical solvothermal process. Compared to pristine Bi 4 O 5 Br 2 nanosheet and NPC-MoS 2 nanorod , the 5 wt% NPC-MoS 2 @Bi 4 O 5 Br 2 p-n heterojunction exhibits distinctly enhanced photocatalytic activity under light illumination due to the increased light absorption capability and more effective charge transfer efficiency. X-ray photoelectron spectroscopy and photoelectrochemical analysis imply that a built-in electric field on interfaces is created to form p-n heterojunctions which drive the photoinduced electrons transferred from NPC-MoS 2 to Bi 4 O 5 Br 2 . Finally, the type-II charge transfer mechanism is proposed which promotes separation of the charges and provides suitable conduction band to reduce CO 2 much efficiently. In a word, this work provides a new insight into the establishment of hierarchical p-n heterostructures for photocatalysis .