介绍了垂直沉降法和旋涂法制备SiO2胶体晶体, 并对两种方法制备的胶体晶体在宏观形貌、微观结构及光子带隙性质进行了比较。采用改进的Stober法在乙醇介质中合成粒径不同、单分散性较好的SiO2微球, 用垂直沉积法和旋涂法制备出有序性较好的密排结构的SiO2胶体晶体。宏观照片表明, 用旋涂法制备的SiO2胶体晶体经白光照射出现的光柱呈6次对称, 而垂直沉降法制备的胶体晶体表面出现条纹。SEM分析表明, 选用不同溶剂在同等旋涂工艺下制备SiO2胶体晶体, 用乙醇和乙二醇混合溶液作溶剂制备出的SiO2胶体晶体质量最好。透射光谱表明, 垂直沉降法所制备的胶体晶体在(111)方向具有明显的光子带隙性质, 而旋涂法制备的胶体晶体则不明显。

SiO2 colloidal crystals were fabricated by vertical deposition and spin coating methods, and their appearance morphology, microstructure and photonic band-gap properties were compared. The used colloidal SiO2 spheres were synthesized by improved Stober method with different diameters and small relative standard deviation. With white light illumination, characteristic six-beam diffraction appears on the SiO2 colloidal crystal fabricated by spin coating, while stripes appear on the surface of the SiO2 colloidal crystal fabricated by vertical deposition. SEM images reveal that, with different dilutions in the same spin coating process conditions, the quality of SiO2 colloidal crystal dispersed in a mixture of glycol and ethanol is best. Transmission measurement shows the colloidal crystal prepared by vertical deposition possesses clear photonic band gap in (111) direction, while the colloidal crystal prepared by spin coating is not the case.