Pfeffermann Martin, Dong Renhao, Graf Robert, Zajaczkowski Wojciech, Gorelik Tatiana, Pisula Wojciech, Narita Akimitsu, Müllen Klaus, Feng Xinliang
Max Planck Institute for Polymer Research , Ackermannweg 10, D-55128 Mainz, Germany.
Center for Advancing Electronics Dresden and Department of Chemistry and Food Chemistry, Technische Universität Dresden , Mommsenstraße 4, D-01062 Dresden, Germany.
J Am Chem Soc. 2015 Nov 18;137(45):14525-32. doi: 10.1021/jacs.5b09638. Epub 2015 Nov 3.
Utilizing dynamic self-assembly and self-sorting to obtain large-area, molecularly precise monolayered structures represents a promising approach toward two-dimensional supramolecular organic frameworks (2D SOF) or 2D supramolecular polymers. So far, related approaches suffer from small domain sizes, fragility and weak long-range internal order. Here we report on the self-assembly of a host-guest enhanced donor-acceptor interaction, consisting of a tris(methoxynaphthyl)-substituted truxene spacer, and a naphthalene diimide substituted with N-methyl viologenyl moieties as donor and acceptor monomers, respectively, in combination with cucurbit[8]uril as host monomer toward monolayers of an unprecedented 2D SOF. Featuring orthogonal solubility, the participating molecules self-assemble at a liquid-liquid interface, yielding exceptionally large-area, insoluble films, which were analyzed by transmission electron microscopy, atomic force microscopy and optical microscopy to be monolayers with a thickness of 1.8 nm, homogeneously covering areas up to 0.25 cm(2), and featuring the ability to be free-standing over holes of 10 μm(2). Characterization with ultraviolet-visible absorption spectroscopy, solid-state nuclear magnetic resonance spectroscopy, infrared spectroscopy, and grazing incidence wide-angle X-ray scattering allowed for confirmation of a successful complexation of all three monomers toward an internal long-range order and gave indications to an expected hexagonal superstructure. Our results extend the existing variety of two-dimensional soft nanomaterials by a versatile supramolecular approach, whereas the possibility of varying the functional monomers is supposed to open adaptability to different applications like membranes, sensors, molecular sieves, and optoelectronics.
利用动态自组装和自分类来获得大面积、分子精确的单层结构，是通往二维超分子有机框架（2D SOF）或二维超分子聚合物的一种很有前景的方法。到目前为止，相关方法存在畴尺寸小、易碎和长程内部有序性弱的问题。在此，我们报道了一种主客体增强的供体-受体相互作用的自组装，该相互作用由一个三（甲氧基萘基）取代的并四苯间隔基，以及分别作为供体和受体单体的用N-甲基紫精基部分取代的萘二亚胺，与作为主体单体的葫芦[8]脲组合，形成一种前所未有的二维超分子有机框架的单层。由于具有正交溶解性，参与的分子在液-液界面自组装，产生异常大面积的不溶性薄膜，通过透射电子显微镜、原子力显微镜和光学显微镜分析为厚度为1.8 nm的单层，均匀覆盖面积达0.25 cm²，并且能够在10 μm²的孔上自立。用紫外-可见吸收光谱、固态核磁共振光谱、红外光谱和掠入射广角X射线散射进行表征，证实了所有三种单体成功络合形成内部长程有序，并暗示了预期的六边形超结构。我们的结果通过一种通用的超分子方法扩展了现有的二维软纳米材料种类，而改变功能单体的可能性有望开启对膜、传感器、分子筛和光电子等不同应用的适应性。
