Study on the sedimentation self-assembly of colloidal SiO2 particles under gravitational field

Synthetic opals with diameters ranging from 700 to 1200 nm monodisperse colloidal SiO2 particles were prepared. We studied the fabrication and the optical characteristics of the synthetic opals, as well as examined the influence of quantitative flux of the colloidal SiO2 particles and the relationship between it and the crystallization rate of the particles within colloidal suspensions on qualities of synthetic opals.