垂直沉积法制备二氧化硅胶体晶体及其表征

利用垂直沉积法将单分散的二氧化硅胶体微球自组装生长为胶体晶体 ,并用扫描电子显微镜和紫外可见光分光光度计对其显微形貌和光学特性进行了表征 .结果表明二氧化硅微球有序堆积 ,自组装成胶体晶体 ,其结构为FCC密排结构 ,表面为FCC密排结构的 ( 1 1 1 )面 ;反射光谱还表明 ,所制备的胶体晶体的光子带隙位于可见光波段 .与重力沉淀等其他自组装方法相比 ,垂直沉积法制备胶体晶体具有能够用胶体微球粒径和胶体溶液浓度精确控制样品厚度等优点

Fabrication and characterization of silica colloidal crystals by vertical deposition method

A self assembly technique which relies on capillary forces to organize silica colloidal was used to fabricate colloidal crystal multilayers. Crystalline quality and thickness of the film were determined using scanning electron microscopy (SEM) and the optical properties of the film were evaluated using UV visible spectrometer. The results show that the colloidal crystals are in FCC structure and the (111) planes of the FCC lattice are parallel to the solid substrates. The reflect spectra in the visible regions show distinct peaks due to the existence of photonic band gap. The results suggest that the colloidal crystal multilayers fabricated by the vertical deposition method have the advantage that the thickness of the resulting sample can be precisely dictated through control of sphere size and concentration in solution.