Process parameter effects on particle size reduction of sol-gel synthesized silica nanoparticles

Abstract

Abstract In present study, SiO2 nanoparticle was prepared using sol-gel method. Tetraethyl orthosilicate (TEOS) was chosen as a silica precursor, ethanol as a solvent, water as co-solvent and ammonia as a catalyst. The effects of most influencing process parameters molar ratio (0.5, 1 and 2) of tetra-(ethyl)-orthosilicate (TEOS) to ammonia (NH3) with respect to particle size variation was investigated experimentally in detail. The size of SiO2 particles was controlled by tuning the NH3 concentration with respect to TEOS. Scanning electron microcopy (SEM) studies were performed for understanding the size of SiO2 nanoparticles while surface functional groups was determine by Fourier transform infrared (FTIR). The amorphous phase and purity of particles was identified by X-ray diffraction (X-RD) and energy dispersive spectroscopy (EDS) respectively. This work demonstrates the molar ratio variation had the noticeable effect on particle size reduction of SiO2 particles. it was found that the particle size decreases with increases of NH3 concentration with respect to TEOS (molar ratio = 1) and found lowest particle size of 40 nm (TEOS: NH3) with fixed amount of TEOS, ethanol, water and reaction time