N-doped titania is prepared using ethylenediamine as the nitrogen source by a sol-gel method. The preparation conditions, such as the volume ratio of ethylenediamine to sol, and the heat temperature on the nitrogen doping are systematically examined. UV results indicate the N-doped TiO2 catalysts have enhanced absorption in the visible light region, and exhibit high activities on the visible light photocatalytic reactions to the hydrogen production and methyl orange degradation. X-ray diffraction (XRD) and FT-IR results reveal that N species have been incorporated into the TiO2 lattice at a high N-doping level. N-doped titania prepared with an ethylenediamine to sol volume ratio of 1:1 and sintering temperature of 500 degrees C performed the highest hydrogen production rate (2.98 mmol g(-1) h(-1)) and best methyl orange degradation performance. A conceivable structure change of N-doped TiO2 sintered at different temperature was proposed. (C) 2015 Elsevier B.V. All rights reserved.