当前位置:科学网首页 > 小柯机器人 >详情
离子溶剂化笼聚合物膜的多样性定向合成
作者:小柯机器人 发布时间:2021/4/11 14:05:13

美国劳伦斯伯克利国家实验室的Brett A. Helms团队的一项最新研究提出了基于离子溶剂化笼的聚合物膜的多样性定向合成。 相关论文于2021年4月7日发表于国际顶尖学术期刊《自然》杂志上。

课题组描述了微孔聚合物膜的多样性定向合成策略,以鉴定具有FVE的候选物,这些FVE可用作锂离子(Li)的溶剂笼。这一策略包括通过Mannich反应使双(邻苯二酚)单体多样化,从而在FVEs中引入Li+配位功能,加强拓扑聚合使FVEs网络进入不同的孔结构,以及多种多样的孔几何和介电性能的聚合物反应。与具有FVE特异性的对照膜相比,具有离子化溶剂笼作为最有前途的候选膜表现出更高的离子电导率和更高的阳离子转移数,表明可以克服常规的膜渗透性和离子迁移选择性的局限性。

这些优势与存在笼子时增强的Li+从电解质中的分配、孔内阴离子的较高的扩散阻挡层以及与本体电解质相比对Li+配位数的网络强制限制有关,这降低了工作离子的有效质量。这种膜在高压锂金属电池中作为阳极稳定夹层显示出了希望。

据了解,微孔菌素聚合物具有形状持久的自由体积元素(FVE),当作为化学分离、水净化、燃料电池和电池的膜时,它们会被小分子和离子渗透。识别具有分析物特异性的FVEs仍然是一个挑战,因为很难生成具有足够多样性的聚合物来筛选它们的特性。

附:英文原文

Title: Diversity-oriented synthesis of polymer membranes with ion solvation cages

Author: Miranda J. Baran, Mark E. Carrington, Swagat Sahu, Artem Baskin, Junhua Song, Michael A. Baird, Kee Sung Han, Karl T. Mueller, Simon J. Teat, Stephen M. Meckler, Chengyin Fu, David Prendergast, Brett A. Helms

Issue&Volume: 2021-04-07

Abstract: Microporous polymers feature shape-persistent free volume elements (FVEs), which are permeated by small molecules and ions when used as membranes for chemical separations, water purification, fuel cells and batteries1,2,3. Identifying FVEs that have analyte specificity remains a challenge, owing to difficulties in generating polymers with sufficient diversity to enable screening of their properties. Here we describe a diversity-oriented synthetic strategy for microporous polymer membranes to identify candidates featuring FVEs that serve as solvation cages for lithium ions (Li+). This strategy includes diversification of bis(catechol) monomers by Mannich reactions to introduce Li+-coordinating functionality within FVEs, topology-enforcing polymerizations for networking FVEs into different pore architectures, and several on-polymer reactions for diversifying pore geometries and dielectric properties. The most promising candidate membranes featuring ion solvation cages exhibited both higher ionic conductivity and higher cation transference number than control membranes, in which FVEs were aspecific, indicating that conventional bounds for membrane permeability and selectivity for ion transport can be overcome4. These advantages are associated with enhanced Li+ partitioning from the electrolyte when cages are present, higher diffusion barriers for anions within pores, and network-enforced restrictions on Li+ coordination number compared to the bulk electrolyte, which reduces the effective mass of the working ion. Such membranes show promise as anode-stabilizing interlayers in high-voltage lithium metal batteries.

DOI: 10.1038/s41586-021-03377-7

Source: https://www.nature.com/articles/s41586-021-03377-7

期刊信息

Nature:《自然》,创刊于1869年。隶属于施普林格·自然出版集团,最新IF:42.778
官方网址:http://www.nature.com/