Gillespie Dirk, Petsev Dimiter N, van Swol Frank
Department of Physiology and Biophysics, Rush University Medical Center, Chicago, IL 60612, USA.
Department of Chemical and Biological Engineering and Center for Micro-Engineered Materials, University of New Mexico, Albuquerque, NM 87131, USA.
Entropy (Basel). 2020 Jan 22;22(2):132. doi: 10.3390/e22020132.
Surprisingly, the local structure of electrolyte solutions in electric double layers is primarily determined by the solvent. This is initially unexpected as the solvent is usually a neutral species and not a subject to dominant Coulombic interactions. Part of the solvent dominance in determining the local structure is simply due to the much larger number of solvent molecules in a typical electrolyte solution.The dominant local packing of solvent then creates a space left for the charged species. Our classical density functional theory work demonstrates that the solvent structural effect strongly couples to the surface chemistry, which governs the charge and potential. In this article we address some outstanding questions relating double layer modeling. Firstly, we address the role of ion-ion correlations that go beyond mean field correlations. Secondly we consider the effects of a density dependent dielectric constant which is crucial in the description of a electrolyte-vapor interface.
令人惊讶的是，双电层中电解质溶液的局部结构主要由溶剂决定。这一现象起初出乎意料，因为溶剂通常是中性物质，不会受到主导的库仑相互作用影响。溶剂在决定局部结构方面占主导地位的部分原因仅仅是典型电解质溶液中溶剂分子的数量要多得多。溶剂的主要局部堆积为带电物种留出了空间。我们基于经典密度泛函理论的研究表明，溶剂结构效应与表面化学强烈耦合，而表面化学决定了电荷和电势。在本文中，我们探讨了与双层建模相关的一些悬而未决的问题。首先，我们探讨了超出平均场关联的离子-离子关联的作用。其次，我们考虑了密度依赖介电常数的影响，这在电解质-蒸汽界面的描述中至关重要。
