Development of heterojunction in N-rGO supported bismuth ferrite photocatalyst for degradation of Rhodamine B

Abstract

A nitrogen-doped graphene oxide (N-rGO) supported bismuth ferrite (BiFeO3/N-rGO) exhibited a superior photocatalytic activity toward degradation of Rhodamine B, which was synthesized by the sol–gel method followed by hydrothermal method. Catalysts were characterized by HR-TEM, X-ray photoelectron spectroscopy (XPS), Fourier transform-infrared (FT-IR), Diffused reflectance spectroscopy (DRS), Electrical impedance spectroscopy (EIS), Photoluminescence (PL) and Mott-Schottky (M−S) analyses. Photoluminescence (PL) spectroscopy confirmed that nitrogen-doped graphene efficiently inhibits recombination of electron-hole pairs in BiFeO3/N-rGO. FTIR, DRS, and XPS analyses confirmed a chemical interaction between graphene and bismuth ferrite leading to the formation of heterojunction. This interaction led to the enhancement of charge transfer for photocatalytic activity. EIS and M−S analyses showed low resistance for charge mobility, high charge carrier density, and high band bending in BiFeO3/N-rGO. A fivefold improvement was observed in the photocatalytic activity of Rhodamine B by using the catalyst as compared to that of bare bismuth ferrite.