title: Free-Standing Monolayer Two-Dimensional Supramolecular Organic Framework with Good Internal Order.
abstract: 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.
authors.affiliation: Max Planck Institute for Polymer Research , Ackermannweg 10, D-55128 Mainz, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Pfeffermann
authors.affiliation: Center for Advancing Electronics Dresden and Department of Chemistry and Food Chemistry, Technische Universität Dresden , Mommsenstraße 4, D-01062 Dresden, Germany.
authors.forename: Renhao
authors.initials: R
authors.lastname: Dong
authors.affiliation: Max Planck Institute for Polymer Research , Ackermannweg 10, D-55128 Mainz, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Graf
authors.affiliation: Max Planck Institute for Polymer Research , Ackermannweg 10, D-55128 Mainz, Germany.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Zajaczkowski
authors.affiliation: Institute for Physical Chemistry, Johannes Gutenberg Universität Mainz , Welderweg 11, D-55099 Mainz, Germany.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Gorelik
authors.affiliation: Max Planck Institute for Polymer Research , Ackermannweg 10, D-55128 Mainz, Germany.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Pisula
authors.affiliation: Max Planck Institute for Polymer Research , Ackermannweg 10, D-55128 Mainz, Germany.
authors.forename: Akimitsu
authors.initials: A
authors.lastname: Narita
authors.affiliation: Max Planck Institute for Polymer Research , Ackermannweg 10, D-55128 Mainz, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Müllen
authors.affiliation: Center for Advancing Electronics Dresden and Department of Chemistry and Food Chemistry, Technische Universität Dresden , Mommsenstraße 4, D-01062 Dresden, Germany.
authors.forename: Xinliang
authors.initials: X
authors.lastname: Feng