The characterization of ag sols by electron microscopy, optical absorption, and electrophoresis

Abstract

Several differently prepared silver sols and a gold sol were examined using electron microscopy optical absorption and microelectrophoresis techniques. The effects of 4-dimethyl-amino-pyridine and pyridine addition to the sols were also studied. In all cases of amine adsorption onto the sol particles, an accompanying decrease in the magnitude of the electrophoretic mobility of the particles was observed, and a long wavelength (>500 nm) absorption band was formed. The solution species responsible for these changes is an aggregate composed of the primary sol. © 1983.