Visible-light-activated C-N-TiO2 powders were synthesized by a facile peptization-reflux method at 120 degrees C. The physical and photophysical properties of the photocatalyst have been characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and UV-vis diffuse reflectance spectra. The as-prepared C-N-TiO2 possessed a diameter of ca. 7 nm with anatase crystalline structure, and showed a shift of the absorption edge to a lower energy and a stronger absorption in the visible region. XPS results indicated that the retained alkoxyl groups existed on the surface of TiO2 and the doped nitrogen incorporated in the TiO2 as formation of N-Ti-O and Ti-O-N. And C-N-TiO2 samples had excellent photocatalytic activity for methyl orange degradation under visible light irradiation, which could be assigned to synergistic effect between the retained alkoxyls and the nitrogen doping. (C) 2013 Elsevier B.V. All rights reserved.