溶胶-凝胶-冷冻法制备纳米TiO2及其表征  

Preparation and characterization of TiO_2 nanopowders by sol-gel freeze-drying process

作　　者：向芸[1,2] 杨世源[2] 梁晓峰[2] 李菊芬[2] 王军霞[2] 文忠和[1] 陈林[1] 徐小勇[1] 

机构地区：[1]萍乡高等专科学校化工系,江西萍乡337000 [2]西南科技大学材料科学与工程学院,四川绵阳621010

出　　处：《材料科学与工艺》2009年第2期281-284,共4页Materials Science and Technology

基　　金：国家自然科学基金资助项目(10476023);四川省科技厅科学基金资助项目(03JY-017)

摘　　要：为解决纳米TiO2粉体易产生团聚的问题,采用溶胶-凝胶与冷冻干燥法制备纳米TiO2粉体.通过X射线衍射、扫描电子显微镜和紫外分光光度计对纳米TiO2粉体的物相组成、形貌和光催化活性进行了表征.实验结果表明:在400℃下所制得的TiO2纳米粉体的粒径约为6 nm,且粒度分布均匀,呈球形;所制得的TiO2纳米粉体在投加量为2 g/L时可使质量浓度为20 mg/L的甲基橙溶液在2.5 h内几乎全部降解.溶胶-凝胶与冷冻干燥法再结合阶段升温焙烧法可得到分散性好、粒径小和光催化活性好的粉体.In order to solve the reunion problem of TiO2nanopowders, the TiO2 nanopowders were prepared by sol-gel freeze-drying process. The phase composition, mierostructure and photocatalytie activity of TiO2 nanopowders were characterized by XRD, SEM and UV-Vis. The results indicate that the mean particle size of TiO2 nanopowders prepared at 400°C is 6 nm, and the TiO2 nanopowders have globose and uniform distribution. When the TiO2 addition is 2 g/L, the methyl orange solution with mass concentration of 20 mg/L can be degraded almost entirely in 2.5 h. Thus TiO2 nanopowders with better dispersibility and smaller mean particle size can be obtained by sol-gel freeze-drying process combined with phase-temperature process.

关 键 词：溶胶-凝胶-冷冻干燥 纳米TIO2 光催化活性 

分 类 号：O643[理学—物理化学]