Preparation of Hollow Mesoporous Silica Microspheres Using Polystyrene Microspheres as Templates

The modulation of the morphological characteristics of hollow mesoporous silica microspheres (HMSMs) plays a crucial role in determining their properties and subsequent applications. In this study, emulsion polymerization was used to fabricate polystyrene microspheres (PSMs) as the primary templating agents. The HMSMs were then successfully synthesized by employing tetraethyl orthosilicate (TEOS) as the silica precursor, with electrostatic interactions driving the process. A range of characterization techniques, including Fourier Transform Infrared Spectroscopy (FT-IR), Brunauer–Emmett–Teller (BET) surface area and porosity analysis, and Transmission Electron Microscopy (TEM), were employed to provide a comprehensive assessment of the PSMs and HMSMs, focusing on their size distribution, structural integrity, and functional properties. The results highlight the importance of the TEOS to PSMs mass ratio, with an optimal value of 0.75. This synthesis yielded HMSMs characterized by exceptional dispersibility and uniformity, with an average diameter of 336.33 nm and a shell thickness of 14.52 nm. Furthermore, the study elucidates the detailed mechanisms of morphological regulation during HMSMs synthesis, driven by the precise control of PSM, TEOS, and cetyltrimethylammonium bromide (CTAB) concentrations. Due to their unique porous structure, tunable pore size, large surface area, and excellent dispersibility, HMSMs show great potential for a wide range of applications, including drug delivery, catalysis, adsorption, and environmental remediation.