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arXiv · 1402.3494

Electrokinetic Instability near Charge-Selective Hydrophobic Surfaces

V. S. Shelistov·E. A. Demekhin·G. S. Ganchenko
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Abstract

The influence of the texture of a hydrophobic surface on the electro-osmotic slip of the second kind and the electrokinetic instability near charge-selective surfaces (permselective membranes, electrodes, or systems of micro- and nanochannels) is investigated theoretically using a simple model based on the Rubinstein-Zaltzman approach. A simple formula is derived to evaluate the decrease in the instability threshold due to hydrophobicity. The study is complemented by numerical investigations both of linear and nonlinear instabilities near a hydrophobic membrane surface. Theory predicts a significant enhancement of the ion flux to the surface and shows a good qualitative agreement with the available experimental data.

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V. S. Shelistov, E. A. Demekhin, G. S. Ganchenko. 2014-02-14. Electrokinetic Instability near Charge-Selective Hydrophobic Surfaces. https://doi.org/10.1103/physreve.90.013001

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