固液界面双电荷层结构的一个界面势模型

A surface potential trap model for the electric double layer at solid—liquid interfaces

当液体受限在纳米尺度下时,会呈现出跟宏观尺度下完全不同的输运性质。这些新的性质可以被应用于很多领域,譬如对生物体中体液输运的研究,液体抽运,药物的混合和分离,以及离子和胶体颗粒的选择等领域。为了充分利用这些新性质,需要对纳米液体中最基本的双电荷层结构有深刻认识。文章回顾了传统的泊松—玻尔兹曼方程对双电荷层结构中液体离子分布的计算,指出了其中的不足,并提出一种基于液体电荷保持中性的固液表面势模型。

Confined nano-scale liquids can display very different behaviors compared to those on the macro scale. These characteristics can have important implications in many areas, such as the transport of biological fluids, liquid pumps with no moving mechanical parts, drug mixing/separation, the selection of colloidal particles, and ion-specific transport through ion chan-nels. The study of the characteristics of nano-fluids requires a thorough understanding of one of the most basic phenomena at fluid-solid interfaces--the electrical double layer （EDL）. This ar-ticle points out some inadequacies in the Poisson-Boltzmann equation that are central to the tra-ditional studies of EDL, and proposes a new framework based on the constraint of global charge neutrality, in conjunction with the introduction of a surface potential trap model.