Simulations of Polyelectrolyte Adsorption to a Dielectric Like-Charged Surface

TL;DR

This study uses Monte Carlo simulations to investigate how polyelectrolytes interact with like-charged dielectric surfaces, revealing the effects of multivalent counterions, salt concentration, and dielectric discontinuity on adsorption behavior.

Contribution

It introduces an efficient simulation method to analyze polyelectrolyte-surface interactions, highlighting the roles of multivalent ions and dielectric effects in adsorption phenomena.

Findings

Multivalent counterions promote strong polyion adsorption.

Adding 1:1 salt reduces multivalent ion-induced adsorption.

Dielectric discontinuity has minimal impact on adsorption.

Abstract

We explore, using the recently developed efficient Monte Carlo simulation method, the interaction of an anionic polyelectrolyte solution with a like-charged dielectric surface. In addition to polyions, the solution also contains salt with either monovalent, divalent, or trivalent counterions. In agreement with recent experimental observations, we find that multivalent counterions can lead to strong adsorption of polyions onto the surface. On the other hand, addition of a 1:1 electrolyte diminishes the adsorption induced by the multivalent counterions. Dielectric discontinuity at the interface is found to play only a marginal role in polyion adsorption.