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Copyright Brian J. Kirby. With questions, contact Prof. Kirby here. This material may not be distributed without the author's consent. When linking to these pages, please use the URL http://www.kirbyresearch.com/textbook.

This web posting is a draft, abridged version of the Cambridge University Press text. Follow the links to buy at Cambridge or Amazon or Powell's or Barnes and Noble. Contact Prof. Kirby here. Click here for the most recent version of the errata for the print version.

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Jump To: [Kinematics] [Couette/Poiseuille Flow] [Fluid Circuits] [Mixing] [Electrodynamics] [Electroosmosis] [Potential Flow] [Stokes Flow] [Debye Layer] [Zeta Potential] [Species Transport] [Separations] [Particle Electrophoresis] [DNA] [Nanofluidics] [Induced-Charge Effects] [DEP] [Solution Chemistry]

9.8 Supplementary reading [electrical double layer top]

This chapter is focused on the Gouy-Chapman description of the diffuse electrical double layers. The double layer theory presented here, combined with the presentation of electroosmosis in Chapter 6, constitutes our first foray into the description of fluid flow past a surface in chemical equilibrium with one-way coupling, i.e., where the electrical double layer induces flow but the flow leaves the electrical double layer unaffected. This description is our first presentation of the classical theory of linear electrokinetics, and has been presented by a number of authors in several useful resources. The Gouy-Chapman double layer theory is named after Gouy [78] and Chapman [79], who presented early versions of the theory. The electrical double layer is discussed in the context of fluid flow in electrolyte solutions in Probstein’s physicochemical hydrodynamics text [29] and Hunter’s texts [4950]. Bard and Faulkner [36] present the electrical double layer in the context of electrochemistry and electrical double layers at electrodes. Israelachvili [80] presents the electrical double layer in the generalized context of surface forces, which provides a complementary point of view of the same physics. Colloid science texts, such as Russel’s [64], Hunter’s [50], and Lyklema’s [51] texts, provide detailed double layer info with a view towards surface-surface forces, colloidal stability, and the experimental techniques used to measure interfacial parameters to inform colloidal analysis. A review by Anderson [81] focuses on the motions of particles owing to interfacial phenomena.

We have assumed that the properties of the solution, particularly the electrical permittivity and the viscosity, are uniform throughout. Comments on the limitations of this assumption and proposed models for accounting for this (for example, viscoelectric modeling) can be found in papers by Lyklema [8283] as well as Hunter’s text [49]. Electrochemical texts such as [35] use differential capacitance measurements to address permittivity variations in the electrical double layer. More detail on the structure of these electrical double layers is presented in Chapters 10 and 16.

Stern [84] introduces the concept of the Stern layer and an early equation resulting from modified Poisson-Boltzmann theory. Steric modifications to Poisson-Boltzmann equations using lattice approaches are generally attributed to Bikerman [85] and have been described more recently by Borukhov [86]. Bazant and co-workers have implemented this in great detail with a view towards managing the fluid flow in nonequilibrium electrical double layers developed at electrodes or metallic surfaces [8788]. Rather than the symmetric lattice approach, theories from the state theory of liquids (the Carnahan-Starling equation of state) have also been applied to dense ion packing [89909192]. Other modified Poisson-Boltzmann models include short-range forces between ions [9394] and walls [95969794]. Modifications to Poisson-Boltzmann theories are numerous, and many reviews have been presented [9899100101].

[Return to Table of Contents]



Jump To: [Kinematics] [Couette/Poiseuille Flow] [Fluid Circuits] [Mixing] [Electrodynamics] [Electroosmosis] [Potential Flow] [Stokes Flow] [Debye Layer] [Zeta Potential] [Species Transport] [Separations] [Particle Electrophoresis] [DNA] [Nanofluidics] [Induced-Charge Effects] [DEP] [Solution Chemistry]

Copyright Brian J. Kirby. Please contact Prof. Kirby here with questions or corrections. This material may not be distributed without the author's consent. When linking to these pages, please use the URL http://www.kirbyresearch.com/textbook.

This web posting is a draft, abridged version of the Cambridge University Press text. Follow the links to buy at Cambridge or Amazon or Powell's or Barnes and Noble. Contact Prof. Kirby here. Click here for the most recent version of the errata for the print version.


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