Visible light-driven Bi2Sn2O7/reduced graphene oxide nanocomposite for efficient photocatalytic degradation of organic contaminants

In this work, a novel Bi2Sn2O7/reduced graphene oxide (RGO) nanocomposite was synthesized by a one-step hydrothermal method. The prepared composite was characterized by means of powder X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectrometry (EDS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL) emission spectroscopy and electrochemical impedance spectroscopy (EIS). The photocatalytic activity of the Bi2Sn2O7/RGO composite was investigated by the degradation of rhodamine B (RhB) and phenol. An increase in photocatalytic activity was observed for Bi2Sn2O7/RGO composite compared with pure Bi2Sn2O7 under visible light. The enhanced photocatalytic performance of the composite was mainly ascribed to the more effective charge separations and the excellent adsorption capacity of RGO. The composite maintained its ability to degrade pollutants efficiently, even after 4 cycles of photocatalysis. Further study proved that both the holes and hydroxyl radicals were the active species in the degradation process. (C) 2015 Elsevier B.V. All rights reserved.