Enhanced photocatalytic property of BiFeO3/N-doped graphene composites and mechanism insight

Abstract A series of BiFeO 3 /(N-doped) graphene composites are prepared by a facile hydrothermal method. BiFeO 3 /N-doped graphene shows photocatalytic performance superior to that of BiFeO 3 /graphene and pristine BiFeO 3 . The enhanced photo-degradation performance of BiFeO 3 /N-doped graphene are mainly attributable to the improved light absorbance of the composite, abundant active adsorption sites and high electrical charge mobility of N-doped graphene, and the downward band bending of BiFeO 3 at the composite interface. In particular, X-ray photoelectron spectroscopy analyses reveal that the electron energy band of BiFeO 3 is downward bent by 1.0 eV at the interface of BiFeO 3 /N-doped graphene, because of different work functions of both materials. This downward band bending facilitates the transfer of photogenerated electrons from BiFeO 3 to N-doped graphene and prompts the separation of photo-generated electron-hole pairs, leading eventually to the enhanced photocatalytic performance.