Synthesis of Mg-Doped TiO2 nanoparticles under different conditions and its photocatalytic activity.

In this study, TiO(2)- and Mg-doped TiO(2) nanoparticles with different dopant contents were prepared by sol-gel method. The prepared photocatalysts were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) and diffuse reflectance spectroscopy (DRS) techniques. The results of BET analysis indicated a pore diameter of 8 nm and surface area of 48.5 m(2) g(-1). XRD patterns of pure and doped TiO(2) nanoparticles at 450 °C revealed that all phases are anatase. The particle size obtained from TEM was less than 20 nm. The band gap energy of Mg-doped TiO(2) nanoparticles was lower than that of TiO(2) . The photocatalytic activity of the pure and doped nanoparticles has been compared in the removal of C.I. Acid Red 27 (AR27). The photocatalytic activity of Mg-doped (0.2 mol%) TiO(2) for the degradation of AR27 was higher than that of bare TiO(2) nanoparticles. Results of total organic carbon analysis and changes in the AR27 UV-Vis peaks indicated 99% mineralization and extinguishing of all peaks in UV and visible regions is possible with Mg-doped TiO(2) nanoparticles. Removal efficiency of AR27 was sensitive to the parameters such as catalyst dose, pollutant concentration and light intensity.