Mesoporous TiO2 (MS-TiO2) spheres were prepared by a sol-gel assisted hydrothermal method using double-surfactant (PEG and F127) as templates. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermal gravimetry, and N2 adsorp-tion-desorption were used for catalyst structural characterization. Phenol was used as a model compound for photocatalytic activity test. The results showed that MS-TiO2 spheres with uniform diameter of 200-300 nm, which was composed by 15-20 run of TiO2 crystals, can be obtained. Maximum specific surface area as high as 106.9 m2/g, together with pore diameter of 6.5-12.6 nm and pore volume of 0.21 cnrVg, can be achieved under the optimum conditions. With increasing calcination temperature, specific surface area and pore volume of MS-TiO2 decreased, and pore diameter enlarged. Double templates can form a more stable spherical micelle, inhibit the growth and particle aggregation of TiO2 precursor and promote its self-assembly into spherical structure. MS-TiO2 prepared at 500℃exhibited the highest activity with the phenol degradation of 86.4%, which is about 1.3 times that of TiO2 without templates.%以聚乙二醇和共嵌段化合物F127为双模板剂,采用溶胶-凝胶辅助水热法制备了球形介孔TiO2 (MS-TiO2).采用扫描电镜、透射电镜、X射线衍射、热重分析和低温N2吸附-脱附对样品进行了结构表征,并以苯酚为降解模型物在紫外光下对其活性进行了评价.结果表明,所得TiO2为球形介孔结构,孔径为6.5～12.6 nm,比表面积最高可达106.9 m2/g,孔体积0.21 cm3/g,球形颗粒直径200～300 nm,由粒径为15～20 nm的小晶粒组成.随着焙烧温度的升高,TiO2的比表面积和孔体积减小,孔径增大.双模板剂的使用比单一模板剂更能形成稳定的立体网状球形胶束,并有效抑制TiO2前驱体的团聚,诱导其形成球形介孔结构.其中,在500℃下焙烧所制MS-TiO2样品表现最高的光催化活性,苯酚降解率达86.4％,为TiO2的1.3倍.
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