中文摘要：

在溶胶-水热法所合成的锐钛矿相TiO2纳米晶基础上,利用模板剂调制的SiO2溶胶进一步合成了多孔SiO2与TiO2复合纳米粒子,重点研究了复合SiO2对纳米锐钛矿相TiO2热稳定性及光催化活性的影响.结果表明,复合SiO2提高了纳米锐钛矿相TiO2的热稳定性,经过900℃热处理后的TiO2仍然具有以锐钛矿相为主的相组成.在光催化降解罗丹明B实验过程中,经过高温热处理的复合纳米材料表现出优于Degussa P25 TiO2的活性,这主要与其锐钛矿相结晶度提高和具有较大比表面积等有关.

英文摘要：

Porous SiO2-TiO2 nanocomposites were synthesized by utilizing TiO2 nanopartilces obtained by a sol-gel method, followed by an impregnation process with F127 modified SiO2 sol. The resulting samples were characterized by XRD, BET, TEM, N2 adsorption-desorption, UV-Vis DRS spectra and FT-IR spectra, and their photocatalytic activities were also evaluated by degrading RhB solution under illumination. The effects of the SiO2 on the thermal stability and photocatalytic activity of anatase nanoparticles were mainly investigated. The results show that the SiO2 can greatly enhance the thermal stability of TiO2 crystallities, even having a principal anatase phase composition after heat-treated at 900℃, and make TiO2 maintain a small crystallite size. The large surface area of the resulting SiO2-TiO2 nanocomposites is attributed to the small crystallite size and porous SiO2. During the processes of photocatalytic degradation RhB, all the as-prepared SiO2-TiO2 nanocomposites by thermal treatment at high temperature exhibit higher activity than Degussa P-25 TiO2. The high activity is attributed to the high anatase crystallinity and the large surface area.