Synthesis and characterization of black TiO2/graphene composites with enhanced photocatalysis

According to the composite design, a series of black TiO 2 /graphene composites were synthesized to improve its photocatalytic activity. TiO 2 is generated in situ on the surface of graphene by a facile sol-gel method. The combination of graphene and TiO 2 was beneficial for eliminating the opportunity of photogenerated electron-hole recombination due to the excellent conductivity of graphene. In the subsequent hydrogenation process, the self-doping Ti 3+ was introduced accompanied by the crystallization of amorphous TiO 2 . The narrowed bandgap caused by self-doping Ti 3+ enhanced the visible light absorption and make the composites appear black. Both of them improved the photocatalytic performance of the synthesized black TiO 2 /graphene composites. The band structure of the composite was analyzed by valence band XPS, revealing the reason for the high visible light catalytic performance of the composite. The results proved that the black TiO 2 /graphene composites synthesized show attractive potential for applications in environmental and energy issues.