One-step synthesis of Cu/N co-doped TiO2 nanocomposites with enhanced photocatalytic activities under visible-light irradiation

In this research, a one-step hydrothermal method is used to prepare Cu-doped, N-doped and Cu/N co-doped titanium dioxide (TiO2) composites, and the doping effects on the structures, absorption and photocatalytic performance are investigated. All the products are in anatase structure. The substitution of Cu atoms in TiO2 and distribution of N in the crystal lattice have been identified by X-ray diffraction, which lead to the decrease of grain size. Hollow micro-nanospheres of Cu-TiO2 samples, which make them have strong dark adsorption properties, can be observed. Cu/N co-doped samples exhibit the maximum light absorption in the visible light region, and a red-shift which is responsible for narrow band gap energy owing to the presence of N-atoms and Cu-atoms in the TiO2 lattice. The synergistic effect of Cu and N results in the enhanced photocatalytic activity for degradation of methyl orange under visible light irradiation.