▎ 摘　　要

TiO2/N-graphene nanocomposites are synthesized via a facile in-situ hydrothermal sal-gel strategy in order to improve the photocatalytic efficiency for pollutant photodegradation under visible light irradiation. The as-prepared nanocomposites are respectively characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and UV-vis diffuse reflectance spectroscopy. Results indicated that neat TiO2 nanoparticles have an average diameter about 6.70 nm while TiO2 nanoparticles in TiO2/N-graphene nanocomposites synthesized through in-situ hydrothermal sol-gel strategy bear an average diameter of nm and are anchored on N-graphene nanosheets via chemical bonding. Both neat TiO2 nanoparticles and chemically anchored TiO2 nanoparticles in TiO2/N-graphene nanocomposites take on the crystal type of anatase. The band gap of TiO2/N-graphene nanocomposites is red-shifted compared with neat TiO2 nanoparticles. The evaluation of photodegradation performance under visible light irradiation suggested that the nanocomposite with 5 wt%N-graphene content has the best visible light photodegradation performance. (C) 2014 Elsevier Ltd. All rights reserved.