Dietzel Mathias, Hardt Steffen
Institute for Nano- and Microfluidics, Center of Smart Interfaces, TU Darmstadt, Alarich-Weiss-Straße 10, D-64287 Darmstadt, Germany.
Phys Rev Lett. 2016 Jun 3;116(22):225901. doi: 10.1103/PhysRevLett.116.225901. Epub 2016 Jun 2.
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 thermovoltages larger in magnitude than for the classical Soret equilibrium.
暴露于温度梯度下的液体电解质扩展相中，电场归因于离子种类不同的热泳迁移率。如本文所示，即使在最简单的电解质中，如果将其限制在带电壁之间，也不需要这种索雷特型离子热扩散来产生热电效应。双电层的空间电荷导致由温度依赖的电泳离子迁移率驱动的选择性离子扩散，对于狭窄通道而言，这种扩散可能导致热电压的幅度比经典索雷特平衡时更大。
