Aggregation in charge-stabilized colloidal suspensions revisited

The Derjaguin-Landau-Verwey-Overbeek (DLVO) theory commonly used to describe interactions bf charged surfaces across liquids has traditionally been reported to fail when used for quantitative predictions of deposition and aggregation in aqueous colloidal suspensions. Yet direct force measurements have recently confirmed the theory down to surface separations of a few nanometers. Aggregation studies on latex and hematite colloids now reconcile these contrasting findings, Well-known discrepancies between theory and experiment with respect to the dependence of aggregation rates on pH (or electrolyte concentration) and particle size are shown to disappear when charge densities are reduced.