Synthesis, characterization and photocatalytic study of graphene oxide and cerium co-doped in TiO 2

The nanocomposite of titanium dioxide (TiO 2 ) combined with graphene oxide (GO) and cerium (Ce) was successfully synthesized via sol–gel method followed by calcining at 300 °C for 2 h. The composite was characterized by X-ray diffraction, ultraviolet–visible diffuse reflectance spectroscopy, scanning electron microscopy (SEM) and Brunauer–Emmett–Teller. The photocatalytic activity was evaluated by photodegradation of methylene blue (MB) under the irradiation of xenon lamp. This study demonstrated that GO and Ce co-doped in TiO 2 could broaden absorption edge to the visible light and increase surface area of samples. SEM observation showed that addition of Ce could solve the problem of the agglomeration of GO under the same experimental conditions. Moreover, the MB photocatalytic degradation rate of the composite with GO doped for 0.2 % and Ce doped for 0.6 % (mass ratio) was up to 97.7 %, which was largely attributed to the synergistic effects in the GO, Ce and TiO 2 system.