核壳结构TiO2／Ag反蛋白石的制备与形貌观察

Preparation and characterization of TiO_2/Ag core-shell structure inverse opals

用化学还原法制备了银包覆聚苯乙烯(PS)微球结构,通过垂直沉积法排列出具有密堆积结构的PS-Ag蛋白石模板,然后采用溶胶-凝胶法渗透TiO2,最后焙烧处理除去PS,制备出了规整的核壳结构TiO2/Ag反蛋白石。采用扫描电镜、透射电镜和X射线衍射对该样品进行了分析。结果表明,PS球表面包覆的为纳米尺度的金属Ag;所制备的PS/Ag核壳微球蛋白石经过480℃、12h焙烧处理后获得的核壳TiO2/Ag反蛋白石结构的单胞参数可以通过调节包覆银层的厚度来调变,即改变AgNO3与PS球的质量比获得具有不同银包覆层厚度、不同单胞参数的三维蛋白石和反蛋白石结构。

Firstly, the polystyrene （PS） microspheres with silver shell were synthesized by chemical reduction method. Subsequently,PS/Ag core-shell opals template was prepared using vertical deposition method, then TiO2 infiltrated into opal template by sol-gel method. Finally the samples were calcinated to remove PS micro- spheres, leaving TiO2/Ag inverse opal. The samples were characterized and investigated by SEM, TEM and XRD. The results showed that the surface of PS microspheres was coated by nano-silver;the unit cell parame- ters of the obtained TiO2/Ag core-shell inverse opals after calcination at 480℃ for 12h can be controlled by ad- justing the shell thickness of silver. In other words, PS/Ag microspheres with different shell thickness of sil- ver, three-dimensional opals and inverse opals structure with different unit cell parameters can be obtained only by tuning AgNO3/PS mass ratio.