Preparation of Hollow Silica Nanoparticles Using Ultrasonically Generated Microbubbles as a Template

抄録

Hollow particles contain a void structure and exhibit unique properties, such as greater thermal and acoustic insulation properties, a lower dielectric constant, and distinct optical properties. Among various hollow particles, those in which the shell material is silica are called hollow silica particles. In this study, we fabricated silica hollow particles by generating microbubbles with an ultrasonic generator. A silica shell was formed at the gas—liquid interface of microbubbles because of hydrolysis and condensation of methyltrimethoxysilane (MTMS), resulting in the formation of hollow silica particles. In addition, we examined the effect of changing the concentration of MTMS vapor in the dry air and the type of carrier gas on the hollow particle formation. As a result, it has been revealed that the adjustment of the MTMS vapor concentration leads to an increase in the yield of hollow silica particles. It has also been shown that the yield of hollow particles is improved by changing the carrier gas to one with low solubility in the liquid.