Moradi Mina, Opara Nadia L, Tulli Ludovico G, Wäckerlin Christian, Dalgarno Scott J, Teat Simon J, Baljozovic Milos, Popova Olha, van Genderen Eric, Kleibert Armin, Stahlberg Henning, Abrahams Jan Pieter, Padeste Celestino, Corvini Philippe F-X, Jung Thomas A, Shahgaldian Patrick
Institute of Chemistry and Bioanalytics, School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland, Hofackerstrasse 35, CH-4132 Muttenz, Switzerland.
Laboratory for Micro- and Nano-technology, Paul Scherrer Institute, Villigen CH-5232, Switzerland.
Sci Adv. 2019 Feb 22;5(2):eaav4489. doi: 10.1126/sciadv.aav4489. eCollection 2019 Feb.
Stable, single-nanometer thin, and free-standing two-dimensional layers with controlled molecular architectures are desired for several applications ranging from (opto-)electronic devices to nanoparticle and single-biomolecule characterization. It is, however, challenging to construct these stable single molecular layers via self-assembly, as the cohesion of those systems is ensured only by in-plane bonds. We herein demonstrate that relatively weak noncovalent bonds of limited directionality such as dipole-dipole (-CN⋅⋅⋅NC-) interactions act in a synergistic fashion to stabilize crystalline monomolecular layers of tetrafunctional calixarenes. The monolayers produced, demonstrated to be free-standing, display a well-defined atomic structure on the single-nanometer scale and are robust under a wide range of conditions including photon and electron radiation. This work opens up new avenues for the fabrication of robust, single-component, and free-standing layers via bottom-up self-assembly.
从（光）电子器件到纳米颗粒和单生物分子表征等多种应用都需要具有可控分子结构的稳定、单纳米级薄且独立的二维层。然而，通过自组装构建这些稳定的单分子层具有挑战性，因为这些体系的内聚仅通过面内键来确保。我们在此证明，诸如偶极 - 偶极（-CN⋅⋅⋅NC-）相互作用等方向性有限的相对较弱的非共价键以协同方式起作用，以稳定四官能杯芳烃的结晶单分子层。所制备的单分子层被证明是独立的，在单纳米尺度上具有明确的原子结构，并且在包括光子和电子辐射在内的广泛条件下都很稳定。这项工作为通过自下而上的自组装制造坚固、单组分且独立的层开辟了新途径。
