Preparation of Ceramic Hollow Particles by Using Vapor-Phase Deposition

Abstract

The present study developed a new route for fabricating ceramic hollow particles by a template method using ceramic coating via chemical vapor deposition (CVD). The CaCO₃ templates were coated with silica layers using a rotary CVD technique, and the hollow particles of silica were formed by removing the templates via acid treatment. The effects of the silica deposition duration by CVD on the microstructure, specific surface area, and pore structure of the silica hollow particles were investigated. The silica hollow particles had 10–30 nm thick silica shells with angular morphologies inherited from those of the templates. The specific surface area of the silica hollow particles increased from 75 to 466 m²/g as the deposition time decreased from 240 to 60 min. Additionally, the preparation of titania hollow particles was demonstrated using CaCO₃ templates coated with titania layers via rotary CVD.