Low temperature preparation and characterization of n-doped and n-s-codoped TiO2 by sol-gel route

This paper reports a new method to prepare the N-doped and N-S-codoped anatase TiO2 photocatalysts at 100 degrees C. The as-prepared photocatalysts were characterized by means of XRD, Raman spectra, TEM, BET, UV-Vis diffuse reflectance spectra (DRS) and XPS. The results showed that the N-doping and N-S-codoping extended the absorbance spectra of TiO2 into visible region with different extent. The BET surface area of the N-S-codoped TiO2 photocatalysts was high up to 245 m(2)g(-1). The results of degradation of methyl orange (MO) solution showed that the N-doped and N-S-codoped TiO2 photocatalysts exhibited higher photocatalytic activity than that of Degussa P-25 and the as-prepared pure TiO2 under visible irradiation. This property can be attributed to the results of synergetic effects of absorption in the visible light region, red shift in adsorption edge, good crystallization and large surface area of the as-prepared N-doped or N-S-codoped TiO2.