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Mg-doped TiO2 mesoporous nanomaterial with high-efficiency solar photoelectric conversion was successfully prepared by a solid-state reaction using cetyltrimethyl ammonium bromide as a template agent. As-prepared Mg-TiO2 nanomaterials are characterized with XRD、SEM, UV-Vis, XPS, BET and Raman spectroscopy. It was found that magnesium as Mg2+ incorporates into the framework of TiO2 by isomorphous replacement with content of 2.36%. The Mg-TiO2 nanoparticles are anatase phase with particle size of 10-24nm. The rod-like nanoparticles have specific surface area of 104.5m2 /g and pore-diameter distribution centre of 5.1 nm. The surface of Mg-TiO2 material with stretching vibrational peak at 1105cm−1 is assignable to the Mg-O-Ti bond. Furthermore, the UV–vis displays that the absorption region of mesoporous Mg-TiO2 powder shifts to 405nm, and the absorption intensity of the visible-light region is enhancement. At 20oC, pH = 6.8, c0 = 50 mg/L, within 150 min, the rule of pseudo-second-order reaction and the degradation rate of thiophanate methyl of 57% and 91.8% corresponding visible-light irradiation and ultraviolet irradiation are obtained for the Mg-TiO2 nanomaterial. But it is poor to photodegradation of thiophanate methyl for P25-TiO2, and it keeps to the rule of pseudo-first-order reaction.

Al and S co-doped TiO2 (S-Al-TiO2) mesoporous materials as a kind of visible light photo- catalysts are prepared using pyridine as a template through a solid state reaction route. The materials features are characterized by the advanced instruments. The photodegradation kinetic of paclobutra- zol is investigated. It is shown that the doping of S and Al could effectively inhibit the growth of anatase TiO2, both S and Al have entered into the lattice of TiO2. Surface area of 81.3m2/g and narrow pore size distribution (~2.1nm) are presented, it not only enables the visible-light absorption but also promotes photocatalytic property of paclobutrazol. Moreover, within 150 min of visible-light irradiation, the photocatalytic degradation of paclobutrazol approximately follows an order kinetics, and the photodegradation rate in 46.7% and reaction rate constant of 0.00414 min-1 are obtained.