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Monodisperse colloidal silica microspheres to have broad application prospects in the field of optics, materials science, biology, etc. Therefore, the preparation and study single-dispersed colloidal silica microspheres has a very important scientific and application value, the use of monodisperse silica colloidal microspheres prepared in the self-assembly properties of colloidal crystals showing excellent properties in the optical, electrical and magnetic fields is the research focus. In this thesis, on the silica colloidal microspheres to carry out the research work, self-assembly. First use Stober sol-gel Monodispersed silica spherical particles of silica particle size, particle size analyzer, scanning electron microscopy study a variety of reaction conditions such as ammonia concentration, the amount of water, TEOS concentration and morphology the effects found with little influence of the particle size of the TEOS concentration; With the increase in the amount of ammonia, the particle size increases, the the monodisperse coefficient also increases significantly; particle size gradually increases with the amount of deionized water, becomes large, the spherical degree of the microspheres becomes better, but the larger amount of water, the spherical degree of variation. The research shows that ammonia and deionized water is the main factor to control the particle size and morphology of the silica microspheres; been analyzed in absolute ethanol for 75ml, TEOS as 15 ml, for 5 ml ammonia water, deionized water, 5ml, preparation of a dispersion, regular shape, spherical colloidal silica particles. Second will receive monodisperse silica spheres vertical deposition method for three-dimensional silica colloidal crystals self-assembled. SEM micrographs of the silica colloidal crystals analysis shows that the self-assembly process temperature, humidity, suspension concentration and other factors have a significant effect on the self-assembly behavior. Temperature is too low, the formation of the colloidal crystals can not be closely arranged and the thickness, the temperature is too high, deterioration of the degree of ordering of the colloidal crystals, cracks, or even Ordering disorganized; humidity increases, the increase in the degree of ordering of the colloidal crystals, defects reduce the suspension sizes concentration; also increased, the thickness of the colloidal crystals. PS template method prepared surface with orderly micro-structure of two-dimensional and three-dimensional silica colloidal crystals, and discuss its formation mechanism; take advantage of the oblique deposition PS-Si02 mixture with a three-dimensional ordered porous structure silica colloidal crystals.
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