arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1701.08151physics.chem-phcond-mat.soft
收藏

在浓缩电解质中筛查不足

Underscreening in concentrated electrolytes

Alpha A. Lee, Carla Perez-Martinez, Alexander M. Smith, Susan Perkin

摘要:

电解质对表面电荷的屏蔽以及由此产生的带电物体之间的相互作用能在从生物分子相互作用到能量存储的场景中具有根本的重要性。传统观点认为,相互作用能随着物体分离呈指数衰减,衰减长度是离子浓度的递减函数;因此,在浓电解质中,相互作用可以忽略不计。与此传统的智慧,我们已经表明,通过表面力测量的衰减长度是一个增加的函数的离子浓度和Bjerrum长度的浓缩电解质。在本文中,我们报告的表面力测量直接测试的Bjerrum长度的屏蔽长度的缩放。此外,我们确定的浓度依赖性的屏蔽长度和经验测量的活度系数和微分电容之间的关系。屏蔽长度对离子浓度和Bjerrum长度的依赖性可以通过基于物理直觉的简单标度推测来解释,即溶剂分子而不是离子是浓电解质中的载流子。

英文摘要:

Screening of a surface charge by electrolyte and the resulting interaction energy between charged objects is of fundamental importance in scenarios from bio-molecular interactions to energy storage. The conventional wisdom is that the interaction energy decays exponentially with object separation and the decay length is a decreasing function of ion concentration; the interaction is thus negligible in a concentrated electrolyte. Contrary to this conventional wisdom, we have shown by surface force measurements that the decay length is an increasing function of ion concentration and Bjerrum length for concentrated electrolytes. In this paper we report surface force measurements to test directly the scaling of the screening length with Bjerrum length. Furthermore, we identify a relationship between the concentration dependence of this screening length and empirical measurements of activity coefficient and differential capacitance. The dependence of the screening length on the ion concentration and the Bjerrum length can be explained by a simple scaling conjecture based on the physical intuition that solvent molecules, rather than ions, are charge carriers in a concentrated electrolyte.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑