In recent years, significant effort has been focused on the production of visible-light activated photocatalysts such as N-doped TiO2 for advanced oxidation processes. Thus, this paper describes a facile and simple route to produce N-doped TiO2 nanoparticles by a modified polymeric precursor method using urea. In addition, the paper describes the characterization and photocatalytic activity evaluation of N-doped TiO2 nanoparticles. The predominance of the anatase phase and the modification of band-gap energies in N-TiO2 indicate that the doping process is effective: Raman spectroscopy shows bands related to TiOxN1-x. The presence of N in higher amounts in the doped nanoparticles confirms the doping process which was also confirmed by X-ray photonelectron spectroscopy (XPS). Unmodified TiO2 nanoparticles indicate higher UV-C photocatalytic activity, and the N-doped TiO2 nanoparticles show better visible photocatalytic activity, suggesting a useful way to operate those catalysts under visible light and/or sunlight. (C) 2011 Elsevier B.V. All rights reserved.