Construction of Br-Cu2O@NiFe-LDHs Z-scheme heterojunction and photocatalytic degradation of catechol

Abstract

Facet regulation and construction of heterojunctions are important means to enhance the photocatalytic performance of single-phase materials. In this paper, the facet index of CuO was changed through Br doping, and then a Br doped CuO@NiFe-LDHs Z-scheme heterojunction (BC@LDHs) was constructed for photocatalytic degradation of catechol. The optimal conditions for photocatalytic degradation reaction were explored; the kinetic and thermodynamic parameters of the reaction, as well as the stability and reusability of the material were studied. Under optimal reaction conditions, the photocatalytic degradation of catechol can reach up to 95.68 % by BC@LDHs, which is much higher than that of single-phase materials and CuO@LDHs. By combining experiments and theoretical calculations, the intrinsic reasons and mechanisms for Br doping to enhance the photocatalytic degradation performance of BC@LDHs Z-scheme heterojunctions were fully explored from the perspectives of band structure and oxygen adsorption, determination of built-in electric field in Z-scheme heterojunctions, calculation of built-in electric field strength and bulk charge separation efficiency. This work proposes the insights that using Br doping to alter exposed facets and regulate the strength of the built-in electric field in Br-CuO@NiFe-LDHs heterojunctions, thereby promoting its efficient photocatalytic degradation.