Comparison of zeta potentials and structure for statistical mechanical theories of a model cylindrical double layer
Article

 Overview

 Research

 Identity

 Additional Document Info

 View All

Overview
abstract

The zeta potential and the structure of a model cylindrical double layer obtained through the PoissonBoltzmann theory, the hypernetted chain/mean spherical approximation integral equation theory, the modified PoissonBoltzmann theory, and the density functional theory are compared with the corresponding Monte Carlo simulation results. The cylindrical double layer consists of an infinitely long cylinder with a uniform surface charge immersed in a restricted primitive model electrolyte (equisized, rigid spherical ions in a continuum dielectric). Calculations have been performed at room temperature and in a waterlike solvent for 1:1, 2:2, 2:1/1:2 valency electrolytes for different electrolyte concentrations, axial charge parameters (surface charge densities), and ionic diameters. The results for the zeta potential, the mean electrostatic potential, and the electrodeion singlet distributions predicted by the formal statistical mechanical theories reproduce the simulation data to a high level of accuracy overall for the range of physical parameters studied. The theoretical predictions, except that due to the classical mean field theory, also reveal a remarkable consistency among themselves. The results also (a) explore the relationship between the occurrence of charge reversal and the negative derivative of the mean electrostatic potential,(b) provide insight into the connection between reversed and extremal values of the zeta potential versus surfaced charge density curves and some aspects of electrokinetics, viz., inverted electrophoretic velocities and the possible existence of differently charged colloids with the same mobility, and (c) suggest a plausible identification of the integrated surface charge density at a point near the cylindrical polyion surface with the electrokinetic charge. © 2017 Elsevier B.V.
publication date
funding provided via
published in
Research
keywords

Cylindrical double layer; Density functional theory; Hypernetted chain; Modified PoissonBoltzmann; Zeta potential Boltzmann equation; Chains; Charge density; Electrodynamics; Electrohydrodynamics; Electrolytes; Electromagnetic fields; Electroosmosis; Electrophoretic mobility; Integral equations; Intelligent systems; Mean field theory; Monte Carlo methods; Poisson equation; Surface charge; Zeta potential; Double layers; Electrolyte concentration; Electrostatic potentials; Hyper netted chains; Hypernetted chain/mean spherical approximations; PoissonBoltzmann; Restricted primitive model; Statistical mechanical theory; Density functional theory
Identity
Digital Object Identifier (DOI)
Additional Document Info
start page
end page
volume