title: Ultrahigh surface area nanoporous silica particles via an aero-sol-gel process.
abstract: We describe a new salt-assisted aero-sol-gel approach to produce spherical nanosized mesoporous silica particles. As an alternative to expensive templating mediums in prior works, salt (NaCl) was employed as a templating medium because it is thermally stable, recyclable, and easily leached. Furthermore, we demonstrate the ability to carry out traditional sol-gel chemistry within an aerosol droplet. The role of salt in sol-gel chemistry and aerosol processing was investigated as a function of hydrolysis time. It was verified that salt accelerates the kinetics of silica gelation, and simultaneously becomes an excellent templating medium to support nano-sized pores inside silica structures in the aerosol processing route. The presence of salt results in a roughly ten-fold increasing in the pore specific surface area and pore volume, subsequent to leaching of the salt matrix. The surface area and pore volume of the as-produced nanoporous silica particles was found to increase with increasing sol-gel hydrolysis time.
authors.forename: S H
authors.initials: SH
authors.lastname: Kim
authors.forename: B Y H
authors.initials: BY
authors.lastname: Liu
authors.forename: M R
authors.initials: MR
authors.lastname: Zachariah
mesh_terms: D000336:Aerosols / Q000737:chemistry*; D005782:Gels / Q000737:chemistry; D006868:Hydrolysis; D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D000336:Aerosols; D005782:Gels; D012822:Silicon Dioxide