Construction of UiO-66/Bi4O5Br2 Type-II Heterojunction to Boost Charge Transfer for Promoting Photocatalytic CO2 Reduction Performance

One of the basic challenges of CO₂ photoreduction is to develop efficient photocatalysts, and the construction of heterostructure photocatalysts with intimate interfaces is an effective strategy to enhance interfacial charge transfer for realizing high photocatalytic activity. Herein, a novel UiO-66/Bi₄O₅Br₂ heterostructure photocatalyst was constructed by depositing UiO-66 nanoparticles with octahedral morphology over the Bi₄O₅Br₂ nanoflowers assembled from the Bi₄O₅Br₂ nanosheets via an electrostatic self-assembly method. A tight contact interface and a built-in electric field were formed between the UiO-66 and the Bi₄O₅Br₂, which was conducive to the photo-electrons transfer from the Bi₄O₅Br₂ to the UiO-66 and the formation of a type-II heterojunction with highly efficient charge separation. As a result, the UiO-66/Bi₄O₅Br₂ exhibited improved photocatalytic CO₂ reduction performance with a CO generation rate of 8.35 μmol h^-1 g^-1 without using any sacrificial agents or noble co-catalysts. This work illustrates an applicable tactic to develop potent photocatalysts for clean energy conversion.