Thermoelectricity in confined liquid electrolytes

Mathias Dietzel; Steffen Hardt

doi:10.1103/physrevlett.116.225901

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arXiv · 1511.09386

Thermoelectricity in confined liquid electrolytes

Mathias Dietzel·Steffen Hardt

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Abstract

The electric field in an extended phase of a liquid electrolyte exposed to a temperature gradient is attributed to different thermophoretic mobilities of the ion species. As shown herein, such Soret-type ion thermodiffusion is not required to induce thermoelectricity even in the simplest electrolyte if it is confined between charged walls. The space charge of the electric double layer leads to selective ion diffusion driven by a temperature-dependent electrophoretic ion mobility, which -- for narrow channels -- may cause thermo-voltages larger in magnitude than for the classical Soret equilibrium.

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Mathias Dietzel, Steffen Hardt. 2015-11-30. Thermoelectricity in confined liquid electrolytes. https://doi.org/10.1103/physrevlett.116.225901

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