Epitaxial growth of Bi4Ti3O12-BiPO4 Z-scheme heterojunction to promote carrier transfer for photocatalytic oxidation of NO

The lack of compactness in heterojunction interfaces and poor charge separation is a great challenge in developing high-efficiency heterojunction photocatalysts . Herein, a novel Bi 4 Ti 3 O 12 -BiPO 4 heterojunction was successfully prepared for the first time by epitaxial growth of BiPO 4 on the surface of Bi 4 Ti 3 O 12 nanosheets . The optimized Bi 4 Ti 3 O 12 -BiPO 4 -0.5 increased the NO oxidation efficiency to 73.05%, surpassing pure Bi 4 Ti 3 O 12 (63.45%) and BiPO 4 (8.35%). Experiments and theoretical calculations indicated that the closely contacted heterointerface between BTO and BPO promoted the generation of the built-in electric field, which led to the formation of the Z- scheme transfer pathway for the photogenerated carriers . Therefore, the separation of photogenerated carriers was facilitated while retaining high redox potential , generating more ·O 2 – and ·OH to participate in NO oxidation. Furthermore, the adsorption of NO and O 2 was enhanced by introducing BiPO 4 , further improving the photocatalytic NO oxidation performance. This work emphasizes the critical role of heterointerface in accelerating charge transfer, providing a basis for the design and construction of tightly contacted heterojunction photocatalysts .