Analysis of parameters and interaction between parameters in preparation of uniform silicon dioxide nanoparticles using response surface methodology

This research makes use of tetraethylortho-silicate (TEOS) to synthesize silicon dioxide (SiO2) nanoparticles with the sol-gel process. During the discussions of reactants (TEOS, NH3, H2O, solvent) and reaction conditions (temperature, reaction time), the size of the silicon dioxide particle will be subjected to change with the variation of these preparation parameters. When the concentrations of TEOS and NH3 are reduced and the reaction temperature is increased, the particle size diminishes immediately. The particle size rises first and then declines along with the water concentration increment. Because of the rise in the value of the solvent's dielectric constant, the synthesized silicon dioxide particles are smaller. The concentrations of NH3 and H2O increment will achieve a more uniform particle size. To synthesize the silicon dioxide particles in the nano class, the concentrations of TEOS, H2O, and NH3 need to be reduced. The preparation parameters should be chosen under the relatively higher reaction temperature, and solvents with lower dielectric constants should not be chosen. The aim of this experiment is to understand the influence of particular factors (NH3 concentration, H2O concentration, reaction temperature) on the target function (particle size and its distribution) and to determine the interaction between factors by using the response surface methodology (RSM). It is shown that the above three factors have notable influences on particle size and that the concentration of NH3 has a more notable influence on the particle size distribution.