Bilayer nanographene reveals halide permeation through a benzene hole

• 成果类型: Article
• 署名作者: Niyas, M. A.; Shoyama, Kazutaka; Gruene, Matthias; Wuerthner, Frank
• 署名单位: University of Wurzburg; University of Wurzburg
• 刊物名称: Nature
• ISSN/ISSBN: 0028-1384
• DOI: 10.1038/s41586-024-08299-8
• 发表日期: 2025-01-23
• 关键词: water desalination; graphene; chloride; binding; anions; nmr

摘要

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.