Fabrication of TiO 2 hollow microspheres(TiO 2-HMSs) has attracted considerable attention owing to their low density,high photoreactivity,and easy to separate and reuse. A fluoride-free method for the fabrication of...Fabrication of TiO 2 hollow microspheres(TiO 2-HMSs) has attracted considerable attention owing to their low density,high photoreactivity,and easy to separate and reuse. A fluoride-free method for the fabrication of TiO 2-HMSs is reported by refluxing a mixed solution of H3PW12O40(0.4 mmol),KCl(2.5 mmol) and Ti(SO4)2(2–25 mmol) at 125 °C for 8 h,followed by decomposition of the K3PW12O40(KPW) template in basic solution. The prepared TiO 2-HMSs are characterized by X-ray diffraction,transmission electron microscopy,scanning electron microscopy,Fourier transform infrared spectroscopy,ultraviolet-visible diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy. The activities of the photocatalysts are evaluated by photocatalytic degradation of Brilliant Red X-3B,an anionic dye,under UV irradiation. It is observed that the TiO 2-HMSs exhibit diameters of approximately 0.5–1 μm,and the photocatalytic activity of TiO 2-HMSs initially increases and then decreases with an increasing amount of Ti(SO4)2. The TiO 2-HMSs prepared in the presence of 4 mmol Ti(SO4)2 exhibit the highest photocatalytic activity,which is 2.1 times higher than TiO 2 nanoparticles(prepared in the absence of the KPW template). The enhanced photocatalytic activity of the prepared TiO 2-HMSs is ascribed to the improved crystallization,coupling effect between TiO 2and the residual KPW template,and the unique hollow structures of TiO 2-HMSs.展开更多
基金supported by Program for New Century Excellent Talents in University(NCET-12-0668)the National Natural Science Foundation of China(21373275120977114)~~
文摘Fabrication of TiO 2 hollow microspheres(TiO 2-HMSs) has attracted considerable attention owing to their low density,high photoreactivity,and easy to separate and reuse. A fluoride-free method for the fabrication of TiO 2-HMSs is reported by refluxing a mixed solution of H3PW12O40(0.4 mmol),KCl(2.5 mmol) and Ti(SO4)2(2–25 mmol) at 125 °C for 8 h,followed by decomposition of the K3PW12O40(KPW) template in basic solution. The prepared TiO 2-HMSs are characterized by X-ray diffraction,transmission electron microscopy,scanning electron microscopy,Fourier transform infrared spectroscopy,ultraviolet-visible diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy. The activities of the photocatalysts are evaluated by photocatalytic degradation of Brilliant Red X-3B,an anionic dye,under UV irradiation. It is observed that the TiO 2-HMSs exhibit diameters of approximately 0.5–1 μm,and the photocatalytic activity of TiO 2-HMSs initially increases and then decreases with an increasing amount of Ti(SO4)2. The TiO 2-HMSs prepared in the presence of 4 mmol Ti(SO4)2 exhibit the highest photocatalytic activity,which is 2.1 times higher than TiO 2 nanoparticles(prepared in the absence of the KPW template). The enhanced photocatalytic activity of the prepared TiO 2-HMSs is ascribed to the improved crystallization,coupling effect between TiO 2and the residual KPW template,and the unique hollow structures of TiO 2-HMSs.