二氧化硅人工蛋白石晶体（opal)的制备及其结构性质的研究

运用胶体化学法合成了尺寸可控的二氧化硅（SiO2）亚微米溶胶小球.透射电子显微镜（TEM）结果显示样品平均尺寸可从200nm变化至600nm，单分散性较高、平均标准偏差小于5％.通过自然沉积法，由溶胶SiO2小球自组织晶化制备了人工蛋白石晶体（opal晶体）结构.样品的剖面扫描电子显微镜（SEM）检测表明，样品为面心立方（fcc）结构.分析表明，较高的单分散性和缓慢的沉积过程是SiO2溶胶小球自组织晶化成三维有序结构的关键因素.反射谱中峰位在1320nm处的反射峰的出现，意味着样品在宏观尺度上的有序排列， 关键词： 亚微米二氧化硅溶胶小球 人工蛋白石晶体 方向带隙

Formation and structure of artificial opal based on the colloidal silica sphere

Highly monodispersed colloidal silica spheres in submicrometer sizes were synthesized by a chemical method.The sizes of silica spheres measured by transmission electron microscopy range from 200 to 600 nm in diameter, and its distribution standard deviation is less than 5%.Scanning Electron Microscopy images show that using self-crystallization of the silica spheres, we have successfully obtained artificial opals with the three dimensional close-packed, face-centered cubic (fcc) silica matrixes. Reflection spectra study reveals that artificial opals show (111) directional photonic band-gap features.