Photodecomposition of Methylene Blue by the S, Al Doped TiO<sub>2</sub> Mesoporous Materials

Abstract

Mesoporous sulfur, aluminium doped TiO2 materials (S-Al-TiO2, S-TiO2, Al-TiO2) have been synthesized by solid-state reaction route. The textural properties of the samples are monitored by the X-ray diffraction (XRD), Scanning electron micrography (SEM), Fourier transform infrared spectroscopy (FT-IR), ultraviolet visible light spectroscopy (UV-Vis) and N2-physisorption. Moreover, compared with the pure TiO2, the photodecomposition properties of methylene blue (MB) irradiated with ultraviolet and visible light are presented on the doped TiO2 materials. It is shown that TiO2 doped by sulfur and /or aluminium are mesoporous materials, and the S and Al enter into the crystal lattice of TiO2. At 298K, the rule of pseudo-first-order reaction and excellent visible light catalytic activity are obtained in the photodecomposition of MB on the S-Al-TiO2, S-TiO2, Al-TiO2 and pure TiO2 materials. Interestingly, the reaction rate constant of MB on the S-Al-TiO2 meso- porous nanomaterial is 11.40 times irradiated with the ultraviolet than that with visible light irradiation. But there is 1.42 times corresponding to the pure TiO2. Within 50 min, ultraviolet degradation rate of MB over the S-Al-TiO2 is 98.5%.