Size control of monodisperse hollow ORMOSIL particles using a self-emulsion process

Abstract

Monodisperse, hollow, organically-modified silica particles with a precisely-controlled size were synthesized using a self-emulsion process via a two-step method in an aqueous alcohol solution. The particle sizes were precisely controlled by manipulating synthetic parameters, including the reaction medium, hydrolysis time, catalyst concentration, phenyltrimethoxysilane (PTMS) concentration, and reaction temperature. Hollow particles with average sizes between 70 and 230 nm were obtained. The type of alcohol co-solvent with water and PTMS concentration were two main factors for controlling the particle size and hollow structure, although other reaction parameters were also effective toward fine-tuning the particle size.