A unified mechanism to quantitatively understand silica particle formation from tetraethyl orthosilicate in batch and semi-batch processes.

Factors for controlling sizes of silica particles formed in the hydrolysis and condensation of silicon alkoxides were examined in batch and semi-batch processes with our model previously proposed. Particle sizes in the particle formation were simulated for buffer systems to reduce time-variation in pH. Effectiveness of the buffer system to suppress time-variation in ionic strength was experimentally verified in a silicon alkoxide concentration range of 0.

Electrolyte-added one-pot synthesis for producing monodisperse, micrometer-sized silica particles up to 7 microm.

A facile one-pot synthesis to produce micrometer-sized silica particles with low polydispersity was examined in a semibatch process where an ethanol solution of tetraethyl orthosilicate (TEOS) was continuously supplied to another ethanol solution of water and ammonia containing an electrolyte of LiCl, NaCl, or KCl. Supply rates of the TEOS solution was ranged with the water and electrolyte concentrations, which indicated that the addition of KCl at a low water concentration was effective to increase size of silica particles in a micrometer range. Highly monodisperse silica particles with an average size of 6.