In Situ Characterization of Dehydration during Ion Transport in Polymeric Nanochannels,Journal of the American Chemical Society

当前位置： X-MOL 学术 › J. Am. Chem. Soc. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

In Situ Characterization of Dehydration during Ion Transport in Polymeric Nanochannels
Journal of the American Chemical Society ( IF 14.4 ) Pub Date : 2021-08-25 , DOI: 10.1021/jacs.1c05765
Chenghai Lu _{1,

2} , Chengzhi Hu _{1,

2} , Cody L Ritt ₃ , Xin Hua ₄ , Jingqiu Sun _{1,

2} , Hailun Xia ₄ , Yingya Liu ₄ , Da-Wei Li ₄ , Baiwen Ma _{1,

2} , Menachem Elimelech ₃ , Jiuhui Qu _{1,

2}

Affiliation

The transport of hydrated ions across nanochannels is central to biological systems and membrane-based applications, yet little is known about their hydrated structure during transport due to the absence of in situ characterization techniques. Herein, we report experimentally resolved ion dehydration during transmembrane transport using modified in situ liquid ToF-SIMS in combination with MD simulations for a mechanistic reasoning. Notably, complete dehydration was not necessary for transport to occur across membranes with sub-nanometer pores. Partial shedding of water molecules from ion solvation shells, observed as a decrease in the average hydration number, allowed the alkali-metal ions studied here (lithium, sodium, and potassium) to permeate membranes with pores smaller than their solvated size. We find that ions generally cannot hold more than two water molecules during this sterically limited transport. In nanopores larger than the size of the solvation shell, we show that ionic mobility governs the ion hydration number distribution. Viscous effects, such as interactions with carboxyl groups inside the membrane, preferentially hinder the transport of the mono- and dihydrates. Our novel technique for studying ion solvation in situ represents a significant technological leap for the nanofluidics field and may enable important advances in ion separation, biosensing, and battery applications.

中文翻译：

聚合物纳米通道中离子传输过程中脱水的原位表征

水合离子跨纳米通道的传输是生物系统和基于膜的应用的核心，但由于缺乏原位表征技术，对其在传输过程中的水合结构知之甚少。在这里，我们报告了使用原位修饰的跨膜转运过程中通过实验解决的离子脱水液体 ToF-SIMS 结合 MD 模拟进行机械推理。值得注意的是，通过具有亚纳米孔的膜进行运输不需要完全脱水。水分子从离子溶剂化壳中部分脱落，观察到平均水合数的降低，这使得这里研究的碱金属离子（锂、钠和钾）能够渗透到孔隙小于其溶剂化尺寸的膜中。我们发现在这种空间受限的传输过程中，离子通常不能容纳两个以上的水分子。在大于溶剂化壳尺寸的纳米孔中，我们表明离子迁移率控制着离子水合数分布。粘性效应，例如与膜内羧基的相互作用，优先阻碍一水合物和二水合物的运输。原位代表了纳米流体领域的重大技术飞跃，并可能在离子分离、生物传感和电池应用方面取得重要进展。

更新日期：2021-09-08

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南