Catalytic activity of mesoporous TiO2−xNx photocatalysts for the decomposition of methyl orange under solar simulated light

Using Tween 80 as pore-directing agent, mesoporous TiO2−xNx was prepared via the hydrolysis of TTIP (titanium tetraisopropoxide) in a mixed aqueous solution of isopropanol and acetic acid in the presence of urea. The resulting mesoporous TiO2−xNx was characterized by XRD, N2 adsorption–desorption isotherms, TEM, UV–vis diffuse reflectance spectra and EDS. TEM and N2 adsorption–desorption isotherms showed that the TiO2−xNx has a uniform mesoporous structure. UV–vis spectra revealed that the nitrogen doping caused the absorption edge of TiO2−xNx to shift to the visible region. 10%N–TiO2 exhibited the highest photocatalytic activity for degradation of MO aqueous solution under solar simulated light irradiation.