In this work, monometallic and bimetallic silver and copper impregnated TiO2-P25 nanoparticles were prepared via impregnation method. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy (DRS) and N-2 physisorption techniques were used for the characterization of prepared nanoparticles. The photocatalytic activity was evaluated versus the removal of C.I. Acid Orange 7. Co-impregnated Ag,Cu/TiO2-P25 nanoparticles showed the highest photocatalytic activity compared to Ag/TiO2-P25, Cu/TiO2-P25 and bare TiO2-P25 nanoparticles. The optimum contents of silver and copper for the preparation of co-impregnated Ag,Cu/TiO2-P25 nanoparticles were 1 and 0.03 at. mol%, respectively. The maximum photocatalytic activity of Ag,Cu/TiO2-P25 nanoparticles was obtained for a catalyst calcined at 450 degrees C. (C) 2013 Elsevier B.V. All rights reserved.