Electrical and Physical Characteristics of Silica Nanoparticles in Aqueous Media Affected by Cations Na, Ba and Al

Abstract

The influence of metal cations which have various valences [mono-(Na + ), bi-(Ba 2+ ) and trivalent (Al 3+ )] at different concentrations (0.001–0.1M) on the behaviour of nanosilica (0.5%wt. and 5%wt.) in aqueous media is analyzed using both photon correlation spectroscopy (particle-size distribution) and electrophoresis (zeta potential, ζ). The zeta potential and the particle-size distribution with respect to the particle volume of nanosilica was found to strongly depend on the silica content, concentration, and valence of cations of dissolved salts. An increase in the latter can cause a change in the sign of the zeta potential.