The control of size and morphology of nanosized silica in Triton X-100 based reverse micelle

Nanosized silica was synthesized by the hydrolysis and condensation of tetraethyl orthosilicate (TEOS) in polyoxyethylene (10) tertoctylphenyl ether (Triton X-100)/cyclohexane/ammonia reverse micelle. The effects of [H2O]/[Triton X-100] (R), ammonia concentration on the size and morphology of the spherical silica were investigated thoroughly. The size of silica displayed an interesting variation with the increases of R and ammonia concentration. The smoothness and dispersibility of the spherical silica became better when high R and ammonia concentration were used, but the spherical regularity was not very good. Most interestingly, fiber-like silica has been obtained in the absence of agitation through controlling R and ammonia concentration, and the formation mechanism was discussed. All the results indicate that reverse micelle media possesses the potential to effectively control the size and morphology of the nanomaterials.