ELECTROSTATIC TRAPPING OF A COLLOIDAL MONOLAYER NEAR A CHARGED WALL

The structure of a model colloidal suspension in the vicinity of a charged wall is studied in the framework of the Derjaguin-Landau-Verwey-Overbeek interaction potential and the hypernetted-chain approximation. Here we consider the case of dilute suspension of highly charged macroparticles interacting with weakly repulsive, neutral, and attractive walls. As the wall-particle electrostatic interactions become successively less repulsive, the formation of a monolayer of colloidal particles, strongly adsorbed onto the surface, is predicted by our results. This monolayer of electrostatically confined particles mimic the effect of an effective surface charge distribution adjacent to the wall which, together with the bare wall surface charge, induces on the other, nonconfined, colloidal particles the same local-concentration profile as that in front of a highly charged and repulsive wall.