Preparation of Micrometer‐ to Sub‐micrometer‐Sized Nanostructured Silica Particles Using High‐Energy Ball Milling

Abstract

Nanostructured porous silica particles with sizes in the micrometer to sub‐micrometer range are of great interest due to their potential applications as catalyst supports and nanocomposite materials. However, if these particles are to be used in industry, a process must be developed to affordably produce them on a large scale. This paper reports on a high‐energy ball‐milling process that has been used to create micrometer‐ to sub‐micrometer‐sized mesoporous silica particles starting from a silica xerogel prepared by a surfactant self‐assembly sol–gel process. We have studied various milling conditions such as milling media (zirconia, stainless steel, or steel‐centered nylon balls), milling time, and the presence of surfactants during milling and the resulting effect on particle size and pore structure. Results from transmission electron microscopy, scanning electron microscopy, X‐ray diffraction, light scattering, and nitrogen adsorption demonstrate the feasibility of producing large quantities of nanostructured particles by this simple milling process.