Controlled Growth of Monodisperse Silica Spheres in the Micron Size Range_英文教材.pdf

JOURNAL OF COLLOID AND INTERFACE SCIENCE 26, 62--69 (1968) Controlled Growth of Monodisperse Silica Spheres in the Micron Size Range1 WERNER STOBER, ARTHUR FINK Department of Radiation Biology and Biophysics, Medical School, University of Rochester, New York 14620 A~D ERNST BOHN, Max-Planck-Institut fi~r experimentelle Medizin, GOttingen, Germany Received August 3, 1967 A system of chemical reactions has been developedwhich permits the controlled growth of spherical silica particles of uniform size by means of hydrolysis of alkyl silicates and subsequent condensation of silicie acid in alcoholicsolutions. Ammonia is used as a morphologicalcatalyst. Particle sizes obtained in suspensionrange from less than 0.05t, to 2 ~ in diameter. In many experimental studies which in- and have been described in the literature volve the use of colloidal suspensions of (2). However, no successful attempt has matter in form of hydrosols and aerosols, it been made to generate monodisperse suspen- would be desirable to have the suspended sions of silica particles. A commercial form phase consisting of homogeneous particles of of highly disperse silica produced by com- uniform shape and size. Such monodisperse bustion of silicon tetraehloride in a hydrogen particulate suspensions offer many experi- torch (3) consists of primary silica spheres of mental and theoretical advantages. They sizes below 0.1 u, but they are aggregated to not o