Preparation of Monodisperse Silica Nanoparticles via Controlling the Interphase of Two-Phase Synthesis for Optical Anticounterfeiting Materials

Abstract

Monodisperse silica particles were fabricated by seed synthesis and growth using two-phase synthesis methods and additional growth methods based on the Stober process. The particle size and monodispersity of the silica particles were investigated by changing the reaction time and reactant concentration during seed growth. At the beginning of seed growth, small and large particles were present at the same time; however, the size became more uniform as the reaction proceeded. When the stirring conditions were constant, the size of the silica particles was constant, despite variations in the reactant concentration. Relatively simple methods of manufacturing photonic crystal films via the self-assembly of monodisperse silica particles in a regular lattice were demonstrated. Using photocurable colloidal suspensions, practical methods are presented to produce colloidal photonic crystals with high optical transparency and physical stiffness.