Characterization and Enhanced Visible-Light Photocatalytic Properties of {001} Facets-Exposed TiO2-Reduced Graphene Oxide Nanocomposites.

The efficient visible-light active nanocomposites of {001} facets-exposed TiO2-reduced graphene oxide (RGO) were fabricated by a simple one-step solvothermal approach for application in photocatalytic degradation. The morphology, structure and optical properties of the nanocomposites were well characterized by X-ray diffraction, transmission electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and UV-vis diffuse reflectance spectroscopy. The results indicated that the TiO2 nanoflakes with exposed {001} facets were well-dispersed and contact closely with the surface of graphene sheets via the formation of Ti-O-C bonds. The percentage of the {001} facets which have higher chemistry activity in anatase TiO2 was about 71.3%. The incorporation of RGO with TiO2 increased the light absorption in the whole visible region and displayed a red-shift absorption edge, accelerated the separation of photogenerated electron-hole pairs, furthermore, effectively enhanced the photocatalytic activity of TiO2 under the visible light. The efficiency of the system was significantly influenced by the content of RGO. The optimum content of RGO was 5 wt% for the maximum photocatalytic efficiency.