One-step synthesis of structurally controlled silicate particles from sodium silicates using a simple precipitation process.
Silicate particles with various types of internal structures were prepared via one-pot synthesis. Spherical particles with sizes of 50-100 nm could be obtained by a simple precipitation process with the addition of alcohol to an aqueous sodium silicate solution. By controlling the reaction conditions such as the precipitating solvent (different types of alcohols), reaction time, temperature, and addition rate, spherical silicate particles with hollow, porous, dense internal structures were synthesized without using an external template. In addition, the amount of Na in the silicate particles was effectively reduced by washing with hot water, acid, or ion-exchange resins. Spherical particles maintained their morphologies after heat treatment at 500 degrees C. Electron microscopy, N(2) adsorption/desorption measurements, ICP-OES, XRD analysis, and IR and (29)Si NMR spectrometry were performed to elucidate the chemical and physical properties of the obtained silicate particles. This method of synthesis could provide a commercial route to the simple, economical mass production of silica particles.
Jung
Chan Yoon
CY
Department of Chemical Engineering, Hanyang University, 17 Haeng-dang dong, Seong-dong gu, Seoul 133-791, Korea.
Kim
Jung Soo
JS
Chang
Tae Sun
TS
Kim
Sun Teak
ST
Lim
Hyung Jun
HJ
Koo
Sang Man
SM