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arXiv · 1703.09591

Electrolyte solutions at curved electrodes. I. Mesoscopic approach

Andreas Reindl·Markus Bier·S. Dietrich
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Abstract

Within the Poisson-Boltzmann (PB) approach electrolytes in contact with planar, spherical, and cylindrical electrodes are analyzed systematically. The dependences of their capacitance $C$ on the surface charge density $\sigma$ and the ionic strength $I$ are examined as function of the wall curvature. The surface charge density has a strong effect on the capacitance for small curvatures whereas for large curvatures the behavior becomes independent of $\sigma$. An expansion for small curvatures gives rise to capacitance coefficients which depend only on a single parameter, allowing for a convenient analysis. The universal behavior at large curvatures can be captured by an analytic expression.

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Andreas Reindl, Markus Bier, S. Dietrich. 2017-03-28. Electrolyte solutions at curved electrodes. I. Mesoscopic approach. https://doi.org/10.1063/1.4979947

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