单分散SiO_2胶体球制备及其胶体晶体组装  

Preparation of monodisperse SiO_2 colloidal spheres and the assemble of colloidal crystals with high crystalline quality

作　　者：方俊[1] 王秀峰[1] 程冰[1] 

机构地区：[1]陕西科技大学材料科学与工程学院,陕西咸阳712081

出　　处：《功能材料与器件学报》2007年第4期394-398,共5页Journal of Functional Materials and Devices

基　　金：国家自然科学基金资助项目(No.50372038)

摘　　要：运用胶体化学法在乙醇介质中合成SiO2胶体球,将制得的样品在30℃下用双氧水浸泡处理48h。用扫描电子显微镜(SEM)、傅立叶红外光谱(FT-TR)、Zeta电位仪和标准氢氧化钠滴定法对其形貌、结构和表面电学性质进行分析。结果表明样品平均粒径为292nm,平均标准偏差小于5%;经双氧水浸泡处理后,SiO2胶体球表面羟基数目增多,在水溶液中的Zeta电位从-55.72mV提高到-63.26mV,表面电荷密度从0.19μC/cm2提高到0.28μC/cm2。通过垂直沉积法,在40℃和60%相对湿度条件下制备出有序性较好、密排结构的SiO2胶体晶体。在SEM下,观察到这种胶体晶体是面心立方(fcc)密排结构,其(111)晶面平行于基底。透射光谱表明,所制备的胶体晶体在(111)方向具有光子晶体的不完全带隙性质。Colloidal SiO2 spheres were synthesized by hydrolysis of tetraethyl orthosilicate （TEOS） in the presence of water and ammonia in an alcoholic medium. In order to enhance surface charges of SiO2 spheres, they were immersed into hydrogen peroxide solution （ n202） for 48h at 30℃. SEM shows that the average size of SiO2 colloidal spheres is 292nm, and its distribution standard deviation is less than 5%. FF - IR results indicate that hydroxyl group on the surface of SiO2 spheres has increased through immersing them into H2O2 solution. Zeta potential of the treated SiO2 spheres in water solution is improved from - 55.72mV to - 63.26mV, while surface charge density of the treated SiO2 spheres is enhanced from 0.19μC/cm^2 to 0.28μC/cm^2. SiO2 colloidal crystal was fabricated from aqueous colloidal solution by the vertical deposition method at 40℃ and 60% relative humidity, SEM images show that the sample of SiO2 colloidal crystal is face - centered - cubic （fcc） substrate. Transmission measurement show the existence structure with its （111 ） planes parallel to the of photonic bad gaps, and the center of which is strongly determined by the incident angles.

关 键 词：光子晶体 胶体晶体 垂直沉积法 SiO2胶体球 表面电荷密度 

分 类 号：O734[理学—晶体学]