Synthesis and Characterization of Ultra-Fine Colloidal Silica Nanoparticles

Authors: Qasim, Mohd; Ananthaiah, J.; Dhara, S.; Paik, P.; Das, D.

Source: Advanced Science, Engineering and Medicine, Volume 6, Number 9, September 2014, pp. 965-973(9)

Publisher: American Scientific Publishers

Abstract:

A facile synthesis of colloidal silica nanoparticles of various sizes, employing the hydrolysis and condensation of tetraethyl orthosilicate (TEOS) in absence of any surfactant, is reported. The surfactantfree colloids of SiO2nanoparticles with diameter ∼5–6 nm are stable upto 50 days after synthesis. The effects of different reaction parameters (e.g., concentration of TEOS, water, alcohol and ammonia) on particle sizes have been investigated. Particle sizes have been found to increase with increasing TEOS and ammonia concentration but decrease with increasing water concentration. Obtained products have been characterized through XRD, UV-Vis spectrophotometry, FTIR, HRTEM and FE-SEM. The colloidal stability has been characterized by zeta potential and rheological measurements.