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Hydration interactions: aqueous solvent effects in electric double layers

Yoram Burak·David Andelman
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Abstract

A model for ionic solutions with an attractive short-range pair interaction between the ions is presented. The short-range interaction is accounted for by adding a quadratic non-local term to the Poisson-Boltzmann free energy. The model is used to study solvent effects in a planar electric double layer. The counter-ion density is found to increase near the charged surface, as compared with the Poisson-Boltzmann theory, and to decrease at larger distances. The ion density profile is studied analytically in the case where the ion distribution near the plate is dominated only by counter-ions. Further away from the plate the density distribution can be described using a Poisson-Boltzmann theory with an effective surface charge that is smaller than the actual one.

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BibTeXRIS

Yoram Burak, David Andelman. 2000-07-05. Hydration interactions: aqueous solvent effects in electric double layers. https://doi.org/10.1103/physreve.62.5296

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