DC electrokinetics for spherical particles in salt-free concentrated suspensions including ion size effects

Abstract

We study the electrophoretic mobility of spherical particles and the electrical conductivity in salt-free concentrated suspensions including finite ion size effects. An ideal salt-free suspension is composed of just charged colloidal particles and the added counterions that counterbalance their surface charge. In a very recent paper [Roa et al., Phys. Chem. Chem. Phys., 2011, 13, 3960- 3968] we presented a model for the equilibrium electric double layer for this kind of suspensions considering the size of the counterions, and now we extend this work to analyze the response of the suspension under a static external electric field. The numerical results show the high importance of such corrections for moderate to high particle charges, especially when a region of closest approach of the counterions to the particle surface is considered. The present work sets the basis for further theoretical models with finite ion size corrections, concerning particularly the ac electrokinetics and rheology of such systems.

14 pages, 11 figures

References in corpus (2)

• Electric double layer for spherical particles in salt-free concentrated suspensions including ion size effects
• Ion size effects on the electric double layer of a spherical particle in a realistic salt-free concentrated suspension

Cited by in corpus (4)

• AC-field-induced Polarization for Uncharged Colloids in Salt Solution: A Dissipative Particle Dynamics Simulation
• Electrokinetic and hydrodynamic properties of charged-particles systems: From small electrolyte ions to large colloids
• Electric double layer of colloidal particles in salt-free concentrated suspensions including non-uniform size effects and orientational ordering of water dipoles
• Ion size effects on the electrokinetics of salt-free concentrated suspensions in ac fields