无模板一步水热法制备TiO2中空微球及其光催化性能

Preparation of h-TiO2 hollow microspheres by one step template-free hydrothermal method and its photocatalytic performance

以Ti(SO4)2为原料,引入F-作为壳层厚度控制剂,采用一步无模板水热法成功制备TiO2中空微球(h-TiO2)。利用XRD和SEM检测技术对样品进行表征分析,详细讨论了nTi∶nF摩尔比、水热反应温度和反应时间对h-TiO2微球壳厚的影响。结果表明,当nTi∶nF=1、水热反应温度140oC、水热反应时间14h时,所得h-TiO2微球是粒径为40-50nm的小颗粒组成的直径约为1.8μm、壳厚约50nm的球形中空微球,具有锐钛矿型晶体结构。n2吸附-脱附实验表明,h-TiO2微球具有较大的比表面积(85.5m^2·g^-1),孔径主要分布在2-10nm之间。通过亚甲基蓝(MB)溶液的光催化降解,评价了h-TiO2微球的光催化性能。在高压汞灯照射下,反应40min,MB的降解率达97.3%。应用于水溶液中氯霉素(CP)、磺胺二甲基嘧啶(SMT)和洛美沙星(LFC)抗生素的光催化降解,反应120min,其降解率分别达到90.2%、93.5%和96.7%,说明h-TiO2微球具有较高的光催化降解性能。

Ti(SO4)2 as a raw material,F-as shell thickness control agent,TiO2 hollow(h-TiO2)microspheres were successfully prepared by one step template-free hydrothermal method.The samples were characterized by XRD and SEM.The effects of F-concentration,hydrothermal reaction time and reaction temperature on the shell thickness of h-TiO2 microspheres were discussed in detail.The results showed that the h-TiO2 microspheres were of anatase phase and composed of some small particles with particle size of 40-50 nm,shell thickness about 50 nm and diameter about 1.8μm when the molar ratio n Ti∶n F=1,the hydrothermal reaction temperature was 140 oC and the hydrothermal reaction time was 14 h.The results of BET showed that the h-TiO2 microspheres were of higher specific surface area(85.4 m^2·g^-1),and pore size was mainly distributed between 2-10 nm.Its photocatalytic performance was evaluated by the degradation of methylene blue(MB).The degradation rate of MB could be reached 97.3%at 40 min under high pressure mercury lamp(125 W)irradiation.In addition,The photocatalytic degradation of three antibiotics(chloramphenicol(CAP),sulfamethazine(SMT)and lomefloxacin(LFC))in aqueous solution were further researched,and the degradation rates reached 90.2%(CAP),93.5%(SMT)and 96.7%(LFC)at 120 min,respectively.The results showed that the h-TiO2 microspheres have higher photocatalytic degradation efficiency.