摘要
使用Stber法化学合成了粒径在200-350nm之间的单分散SiO2,采用垂直沉积技术自组装制备了胶体晶体薄膜。通过扫描电镜与分光光度计对样品的微观结构与透过光谱进行了表征,结果表明,组成胶体晶体的SiO2微球呈面心立方结构,膜层的厚度可以通过胶体溶液的浓度加以控制,胶体膜层透射光谱中出现的峰值位置取决于SiO2微球的大小,并且与布拉格定律理论计算的结果相一致,透射光谱中光学阻带的深度可以通过改变胶体悬浮液中SiO2颗粒的体积分数来调控。
The monodisperse silica spheres with diameters of 200-350 nm were synthesized by hydrolysis of tetraethyl orthosilicate based on the Stober process, and silica colloidal crystals was fabricated with a vertical deposition self-assembly method. Scanning electron microscopy and optical transmission spectra were applied to characterize the structures and properties of the deposited films. Experimental results show that the silica spheres form a face-centered cubic structure and the film thickness can be manipulated by controlling the particle concentration. The distinct peaks of transmission spectra for colloidal layers depend on the size of the silica spheres, which are consistent with theoretical calculation according to Bragg’s law. The depth of the optical stop band can be tuned by varying the volume fraction of SiO2 particles in the colloidal suspension.
基金
supported by National Nature Science Foundation of China under grant No.60990320 60990322 and 60801001
关键词
自组装
胶体晶体
垂直沉积
光学性能
SIO2微球
self-assembly
colloidal crystal
vertical deposition
optical property
silica sphere
