Solvothermal Synthesis of SrTiO3-LnTiO2N Solid Solution and Their Visible Light Responsive Photocatalytic Properties

SrTiO3-LnTiO(2)N solid solution, Sr1-xLaxTiO3-yNy, was synthesized by the solvothermal reactions in KOH aqueous solution using [(CH3)(2)CHO](4)Ti, SrCl2 center dot 6H(2)O, La(NO3)(3)center dot 6H(2)O and HMT (hexamethylenetetramine) as raw materials. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric and differential thermal analysis (TG-DTA) and diffuse reflectance spectra. The nano particles of perovskite type Sr1-xLaxTiO3-yNy (x=0, 0.025, 0.05 and 0.1 named as ST, STN-0.025, STN-0.05 and STN-0.1) were successfully synthesized by solvothermal method. The photocatalytic activity of SrTiO3 for DeNO(x) ability in visible light region (>510nm) could be improved by co-doping of La3+ and N3-. The high visible light photocatalytic activity of this substance may be due to generating of a new band gap that enables to absorb visible light. The photocatalytic activity of Sr1-xLaxTiO3-yNy changed with variation of La content. The powder with smaller ratio of La content possessed excellent photocatalytic activity under visible light irradiation.