In this study, nitrogen doped and nitrogen/silver co-doped TiO2 photocatalsysts were fabricated using a sol-gel method at room temperature. The obtained gels were neutralized, washed with pure water, and calcined at 400 degrees C for 4 h. The photocatalysts were characterized by scanning and transmission electron microscopy, X-ray diffracticin, diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, and BET specific surface area. The results showed that spherical particles with anatase structure were produced after annealing at 400 degrees C. N is (400 eV) and Ag 3d (367.3 eV) states indicated that nitrogen doping and silver co-doping were in the form of NO bonds and AgO, respectively. The photocatalytic activity of photocatalysts was investigated using a batch reactor system exposed to artificial solar irradiation. Both nitrogen and silver/nitrogen co-doped materials were effective in the photocatalytic degradation of hexamethyl pararosaniline chloride. (C) 2013 Elsevier Ltd. All rights reserved.