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arXiv · 1703.06643

Solvo-osmotic flow in electrolytic mixtures

Sela Samin·René van Roij
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Abstract

We show that an electric field parallel to an electrically neutral surface can generate flow of electrolytic mixtures in small channels. We term this solvo-osmotic flow, since the flow is induced by the asymmetric preferential solvation of ions at the liquid-solid interface. The generated flow is comparable in magnitude to the ubiquitous electro-osmotic flow at charged surfaces, but for a fixed surface charge density, it differs qualitatively in its dependence on ionic strength. Solvo-osmotic flow can also be sensitively controlled with temperature. We derive a modified Helmholtz-Smoluchowski equation that accounts for these effects.

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Sela Samin, René van Roij. 2017-03-20. Solvo-osmotic flow in electrolytic mixtures. https://doi.org/10.1017/jfm.2017.184

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