TiO2纳米晶多孔微球的制备方法及形成机理

摘要

TiO2纳米晶多孔微球具有颗粒大、晶粒尺寸小及比表面积较高等优点．以明胶作为模板，以钛酸丁酯为原料，采用溶胶⁃凝胶法制备了TiO2纳米晶多孔微球，并采用透射电镜、X射线衍射仪对其性能进行了表征．实验结果表明：采用溶胶⁃凝胶法成功制备了纯锐钛矿型TiO2；明胶的加入对样品的物相组成没有影响，但改变了其晶粒尺寸和排布方式，得到了一种由纳米晶组成的多孔微球；微球直径约为200～500 nm，其中孔隙约为2～5 nm，平均晶粒尺寸为（14�3±0�9） nm．在此基础上对TiO2纳米晶多孔微球的形成机理进行了分析．%Porous TiO2 microspheres with nanocrystalline have the advantages of big grain size,small crystalline size and high specific surface.In this study,porous TiO2 microspheres with nanocrystalline were fabricated by using butyl titanate as raw material and gelatin as a template with the sol⁃gel method.Then their properties were character⁃ized by transmission electron microscope and X⁃ray diffraction. The results showed that the pure anatase TiO2 was gained and its composite was not changed when the gelatin solution was added.However,the gelatin refined and re⁃arranged TiO2 crystallizes.It was demonstrated that porous TiO2 microspheres with the diameter of about 200⁃500 nm were formed,and consisted of nanocrystallizes with the average size of(14�3 ± 0�9)nm and pores about 2⁃5 nm.Mo⁃reover,the formation mechanism of porous TiO2 microspheres was analyzed.