Controlling the Shape, Pore Size and Surface Area of Prepared Mesoporous Silica Particles by Altering the Molar Concentration of Tetramethoxysilane

Abstract

In recent days, the applications of silica-based nanoparticles have gained much attention. The preparation of mesoporous silicas is usually achieved via the modified Stöber method, the reaction attained by the hydrolysis and condensation of silica precursors present within a medium containing template, solvent, deionized water (DI-W) and base. Therefore, the current study aimed to prepare and characterize mesoporous silicas by using tetramethoxysilane (TMOS) as silica precursor and ethylene glycol (Et-G) as solvent. The study was based on the template dodecyltrimethylammonium bromide (C 12 TMABr) and sodium hydroxide used as an alkaline agent. Mesoporous silicas were prepared in various batches based on TMOS molar concentration, ionized water, NaOH, and other solvents. The characterization of mesoporous silicas was achieved based on their specific surface area, pore size distribution and morphology using different instruments: Brunauer, Emmett & Teller (BET), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and thermalgravimetric analysis (TGA). The study revealed that shape, average particle sizes “35 to 550 nm”, average pore radius “1.62 - 4.5 nm” and surface area “350 - 1204 m 2 ·g -1 ” of obtained mesoporous silica particles were altered based on precursor concentration and other factors. Therefore, it is important to get the most suitable concentration of all chemicals in the preparation of mesoporous silicas to control the particle characteristics to use them upon their further applications. This is the baseline study that provides details regarding prepared silica particles with controlled characteristics, and more studies related to its applications are still in process.