Graphene oxide–BiOBr composite material as highly efficient photocatalyst for degradation of methylene blue and rhodamine-B dyes

Abstract

A graphene oxide (GO)/BiOBr composite was successfully synthesized, using a simple two-step process. The tetragonal phase of BiOBr was incorporated into GO sheets, and was employed as a photocatalyst for the degradation of rhodamine-B (RhB) and methylene blue (MB) under visible light. The synthesized composites have been characterized by Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-rays analysis (EDAX), transmission electron microscopy (TEM), Raman spectroscopy and X-ray photoelectron spectroscopic (XPS) studies. The decomposition and degradation of the dyes were visualized by UV–Visible spectroscopy, by decrease in the intensity of absorbance and concentration, substantiated by TOC analysis. The mechanism of photocatalytic effect of GO/BiOBr composite has been also discussed. The degradation efficiency of GO–BiOBr (5%) composite towards MB & RhB was found to be 98% and 95% respectively, when compared to 40% and 50% using pure BiOBr.