A green and facile synthesis of TiO2/graphene nanocomposites and their photocatalytic activity for hydrogen evolution

This work reports a green and facile approach to synthesize chemically bonded TiO2/graphene sheets (GS) nanocomposites using a one-step hydrothermal method. The as-prepared composites were characterized by X-ray diffraction, transmission electron microscopy, Raman spectroscopy and ultraviolet visible (UV-Vis) diffuse reflectance spectra. The photocatalytic activity was evaluated by hydrogen evolution from water splitting under UV–Vis light illumination. An enhancement of photocatalytic hydrogen evolution was observed over the TiO2/GS composite photocatalysts, as 1.6 times larger for TiO2/2.0 wt%GS than that of Degussa P25. This fabrication process features the reduction of graphene oxide and formation of TiO2 simultaneously leading to the well dispersion of generated TiO2 nanoparticles on the surface of GS.

► A hydrothermal method was proposed to obtain chemically bonded TiO2/graphene sheets nanocomposites.
► This method presents a virtue of absence of organic solvent.
► The reduction of graphene oxide and formation of TiO2 is finished at one step.
►  Hydrogen evolution is 1.6 times larger for TiO2/2.0 wt%GS than that of Degussa P25.