Analysis of Parameters and Interaction between Parameters in Preparation of Uniform Silicon Dioxide Nanoparticles Using Response Surface Methodology

Abstract

This research makes use of tetraethylortho-silicate (TEOS) to synthesize silicon dioxide (SiO 2 ) nanoparticles with the sol-gel process. During the discussions of reactants (TEOS, NH 3 , H 2 O, 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 NH 3 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 NH 3 and H 2 O increment will achieve a more uniform particle size. To synthesize the silicon dioxide particles in the nano class, the concentrations of TEOS, H 2 O, and NH 3 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 (NH 3 concentration, H 2 O 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 NH 3 has a more notable influence on the particle size distribution.

Preparation of spherical silica particles by St?ber process with high concentration of tetra-ethyl-orthosilicate

“…As for synthesis process of silica particles, three main types of methods were proposed [9][10][11][12][13][14][15][16][17][18][19]. Pileni [9] prepared silica particles in the size range of tens-hundreds nanometers by using microemulsions method.…”

“…Meanwhile, notable disadvantage of this method is that before reaction, the elemental silicon must be activated by washing with aqueous hydrofluoric acid, pure water, alcohol and ether consecutively to remove silicon dioxide film from the particle surface and to expose a clean silicon surface [15]. Stöber process [11,18] is regarded as the simplest and most effective route to prepare monodisperse silica spheres because the reactants are normal and reaction condition is controllable and is easy to be carried out. Seed growth method derived from Stöber process is mainly used to prepare silica particles of larger than 1 lm.…”

“…Since Stöber prepared silica particles in the range of 0.05-2 lm through the hydrolysis and condensation of alkyl silicates under alkaline conditions in alcoholic solutions [11], many researches were conducted in this area [16][17][18][19]. Chen prepared 73-730 nmsized particles with 0.068-0.22 M TEOS [16].…”

Preparation, characterization and photoluminescence properties of SiO2 and SiO2:Eu3+ submicron rods

“…The dropping speed of NH 4 OH has effects on the formation of template and the hydrolysis and condensation of TEOS. The hydrolysis and condensation increased when dropping NH 4 OH quickly and the nucleating time became shorter so that the particles having little time to reunite but growing along the crystal template [27].…”

Fabrication of Fast‐Absorbing and Quick‐Drying Wool Fabrics with Good Washing Durability

“…The static repulsive force between particles is greater than the van der Waals force when the solvent' s dielectric constant is large. [9] Because the static repulsive force prevents the gathering of the nuclei, the formation of smaller particles on the surface of the wool fiber occurs more easily. The pH is adjusted to 3-4 to protect the wool fiber, which is vulnerable in the base solution at a high temperature.…”