德国维尔茨堡大学Wrthner, Frank团队报道了双层纳米石墨烯揭示卤化物通过苯孔渗透。相关研究成果发表在2025年1月15日出版的《自然》。

石墨烯是一种单层sp²杂化碳同素异形体，它不渗透除氢以外的所有原子。缺陷的引入能够实现选择性气体渗透；开展了大量研究控制这些缺陷的大小以获得更高的选择性。除气体外的其他物质的渗透，如离子，具有根本的科学意义，因为它在海水淡化、检测和净化方面具有潜在的应用。然而，到目前为止，卤化物渗透的精确实验观察仍然未知。

该文中，研究人员展示了卤化物通过分子纳米石墨烯中单个苯大小的缺陷的渗透。利用自聚集的超分子原理，研究人员创建了一个稳定的纳米石墨双层。由于双层纳米石墨烯中的空腔只能通过两个埃大小的窗口进入，因此任何被困在空腔内的卤化物都必须通过单个苯孔渗透。

实验揭示了氟化物、氯化物和溴化物通过单个苯孔的渗透性，而碘化物是不可渗透的。氯化物在单层纳米石墨烯上的高渗透性，和双层纳米石墨烯中的选择性卤化物结合的证据，为石墨烯中单苯缺陷用于人工卤化物受体、作为过滤膜，以及进一步创建多层人工氯化物通道提供了希望。

附：英文原文

Title: Bilayer nanographene reveals halide permeation through a benzene hole

Author: Niyas, M. A., Shoyama, Kazutaka, Grne, Matthias, Wrthner, Frank

Issue&Volume: 2025-01-15

Abstract: Graphene is a single-layered sp2-hybridized carbon allotrope, which is impermeable to all atomic entities other than hydrogen1,2. The introduction of defects allows selective gas permeation3,4,5; efforts have been made to control the size of these defects for higher selectivity6,7,8,9. Permeation of entities other than gases, such as ions10,11, is of fundamental scientific interest because of its potential application in desalination, detection and purification12,13,14,15,16. However, a precise experimental observation of halide permeation has so far remained unknown11,15,16,17,18. Here we show halide permeation through a single benzene-sized defect in a molecular nanographene. Using supramolecular principles of self-aggregation, we created a stable bilayer of the nanographene19,20,21,22,23. As the cavity in the bilayer nanographene could be accessed only by two angstrom-sized windows, any halide that gets trapped inside the cavity has to permeate through the single benzene hole. Our experiments reveal the permeability of fluoride, chloride and bromide through a single benzene hole, whereas iodide is impermeable. Evidence for high permeation of chloride across single-layer nanographene and selective halide binding in a bilayer nanographene provides promise for the use of single benzene defects in graphene for artificial halide receptors24,25, as filtration membranes26 and further to create multilayer artificial chloride channels.

DOI: 10.1038/s41586-024-08299-8

Source: https://www.nature.com/articles/s41586-024-08299-8