Synthesis and Characterization of WO(3)/Graphene Nanocomposites for Enhanced Photocatalytic Activities by One-Step In-Situ Hydrothermal Reaction

Tungsten trioxide (WO(3)) nanorods are synthesized on the surface of graphene (GR) sheets by using a one-step in-situ hydrothermal method employing sodium tungstate (Na(2)WO(4)·2H(2)O) and graphene oxide (GO) as precursors. The resulting WO(3)/GR nanocomposites are characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. The results confirm that the interface between WO(3) nanorod and graphene contains chemical bonds. The enhanced optical absorption properties are measured by UV-vis diffuse reflectance spectra. The photocatalytic activity of the WO(3)/GR nanocomposites under visible light is evaluated by the photodegradation of methylene blue, where the degradation rate of WO(3)/GR nanocomposites is shown to be double that of pure WO(3). This is attributed to the synergistic effect of graphene and the WO(3) nanorod, which greatly enhances the photocatalytic performance of the prepared sample, reduces the recombination of the photogenerated electron-hole pairs and increases the visible light absorption efficiency. Finally, the photocatalytic mechanism of the WO(3)/GR nanocomposites is presented. The synthesis of the prepared sample is convenient, direct and environmentally friendly. The study reports a highly efficient composite photocatalyst for the degradation of contaminants that can be applied to cleaning up the environment.