One-step synthesis of easy-recycling TiO2-rGO nanocomposite photocatalysts with enhanced photocatalytic activity

The addition of reduced graphene oxide (rGO) in the TiO2 has been demonstrated to be one of the effective methods to improve the photocatalytic performance of TiO2 photocatalyst. Despite tremendous efforts, developing facile and green synthetic method of TiO2-rGO nanocomposites still remains a great challenge. In this study, a one-step green hydrothermal method for the fabrication of easily recycled TiO2-rGO composites, based on the initial formation of strong-coupling TiO2-GO nanocomposite and the subsequent in situ reduction of GO to rGO during hydrothermal treatment, was developed in the pure water without using any reductant and surfactant. It is found that the TiO2 nanoparticles with a clean surface and a good dispersion are highly required for the formation of the easy-recycling TiO2-rGO composite photocatalyst. Photocatalytic experimental results indicated that compared with the high-efficiency P25 TiO2 precursor, the photocatalytic performance could be obviously improved (about 23%) for the decomposition of phenol after coupling 1-wt% rGO. The enhanced photocatalytic performance can be attributed the cooperation effect of the effective separation of charge carriers via rGO cocatalyst, the enrichment of phenol molecular on the rGO, and the strong coupling interaction between TiO2 nanoparticles and rGO nanosheets. Considering its completely green and facile preparation and recyclable feature from an aqueous solution, the present TiO2-rGO nanocomposite photocatalyst can be regards as one of the ideal photocatalysts for various potential applications. (c) 2012 Elsevier B.V. All rights reserved.