Effects of Iron and Graphene Oxide on the Photocatalytic activity of Titanium Dioxide for Methylene Blue Degradation

Abstract

Among the photocatalysts, Titanium dioxide (TiO2) is mostly used for wastewater treatment. Nevertheless, large band gap, rapid recombination of electron–hole along with difficult separation process limits TiO2 applications in industrial scale. In this study, the photocatalytic activity and separation of TiO2 were improved by combined application of Fe3O4 and graphene oxide. X-ray powder diffraction (XRD), scanning electron microscopy (FESEM), and magnetization measurement (VSM) was utilized to characterize the sample and the photocatalytic degradation of methylene blue under visible light irradiation was evaluated by UV-vis spectrophotometer. The results indicate the successful preparation of purified TiO2/Fe3O4/GO nanocomposite by a two-step sol gel-hydrothermal method. The enhanced photocatalytic activity of nanocomposite is attributed to the simultaneous application of iron oxide and graphene oxide. The maximum photocatalytic decoloration (90%) is achieved within 80 min under lamp irradiation. The superparamagnetism of nanocomposites provided a convenient route for separation of the catalyst from the reaction mixture by an external magnet.