Synthesis of Nanosized Silica Powder by Ultrasonic Process

Nanosized silica powders were synthesized via w/o emulsion method using sodium silicate as SiO2 source under ultrasonic process. The powders were prepared under conventional process and ultrasonic process using the same reactants at ambient temperature for 1h varying the concentration of Na2SiO3 solution while fixing the concentration of surfactant in cyclohexane. The particle size of the silica powder decreased with decreasing the concentration of sodium silicate solution under both conditions, with and without ultrasounds. However, the particle size and size distribution of the silica powder with ultrasounds were smaller and narrower than those without ultrasounds, establishing that ultrasound treatments decrease the particle size and become narrow in particle size distribution.