Growing single crystal opal films from lyophilic suspensions of monodisperse spherical silica particles

A study was conducted to demonstrate the growth of single crystal opal films from lypophilic suspensions of monodisperse spherical silica particles (MSSP). Dimethylsulfoxide (DMSO) was used as a dispersion medium, to enable the growth of single crystal opal films from MSSPs). The polar molecules of DMSO was used as a surfactant, forming a dense layer of molecules oriented along the normal to the surface of particles. The molecules were strongly bound to the surface of silica particles that imparted lypophilic properties to the MSSPs in the layer of DMSO. These molecules ensured the affinity of the liquid medium to the particle surface. It was found that that it is possible to obtain MSSP single crystals opal films in DMSO, as compared with lypophobic suspensions, with a stop band reflectivity of up to 96%.