GROWTH-KINETICS OF SILVER-CHLORIDE PRECIPITATION IN A NA2O-B2O3 GLASSINVESTIGATED BY MEANS OF SMALL-ANGLE X-RAY-SCATTERING AND TRANSMISSION ELECTRON-MICROSCOPY

The kinetics of silver chloride cluster formation in a sodium berate g lass heat treated isothermally at different temperatures above the gla ss transition temperature has been studied with small-angle X-ray scat tering (SAXS). It is established that the size distributions of partic le number and particle volume have bimodal shapes, i.e. the system of AgCl droplets consists of two populations with significantly different mean radii. The bimodality of the size distribution functions is conf irmed by results of transmission electron microscopy (TEM) even if dif ferent techniques of sample preparation are used. The resolution limit s of the TEM techniques applied amount to 2 nm and are comparable with the smallest particle diameters detectable by the SAXS method. The ev olution of the size distributions is discussed in the framework of the theories of nucleation, growth and Ostwald ripening.