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

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. (C) 2014 Published by Elsevier Ltd.