UV and Visible light photodegradation of methylene blue with graphene decorated titanium dioxide

Abstract

Photocatalytic degradation of methylene blue by graphene decorated titanium dioxide (TiO2) powders heated at different temperatures was analyzed. The powders were prepared by mixing TiO2 with graphene prepared by the modified Hummers method. A thermal treatment was applied to mixed and pure TiO2 powders with the aim of analyze their structural dependence on temperature, and consistently their photocatalytic degradation effect on methylene blue solutions exposed to UV and visible radiation. Structural characterization of the powders was carried out by X-ray diffraction and Raman spectroscopy. When irradiated with UV, the mixed powders showed as high as 87% photocatalytic degradation, while the pure TiO2 reached values of 59%. For visible radiation, as it is expected, the pure TiO2 showed no activity, while the mixture presented degradation of 40%.