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arXiv · 2011.01854

Electroneutrality breakdown in nanopore arrays

J. Pedro de Souza·Amir Levy·Martin Z. Bazant
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Abstract

The electrostatic screening of charge in one-dimensional confinement leads to long-range breakdown in electroneutrality within a nanopore. Through a series of continuum simulations, we demonstrate the principles of electroneutrality breakdown for electrolytes in one dimensional confinement. We show how interacting pores in a membrane can counteract the phenomenon of electroneutrality breakdown, eventually returning to electroneutrality. Emphasis is placed on applying simplifying formulas to reduce the multidimensional partial differential equations into a single ordinary differential equation for the electrostatic potential. Dielectric mismatch between the electrolyte and membrane, pore aspect ratio, and confinement dimensionality are studied independently, outlining the relevance of electroneutrality breakdown in nanoporous membranes for selective ion transport and separations.

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J. Pedro de Souza, Amir Levy, Martin Z. Bazant. 2020-11-03. Electroneutrality breakdown in nanopore arrays. https://doi.org/10.1103/physreve.104.044803

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