Center for Soft Condensed Matter Physics and Interdisciplinary Research and School of Physical Science and Technology, Soochow University, 215006, Suzhou, China.
Department of Physics, Southern University of Science and Technology, 518055, Shenzhen, China.
Nat Commun. 2019 Jan 8;10(1):70. doi: 10.1038/s41467-018-07933-0.
Control over on-surface reaction pathways is crucial but challenging for the precise construction of conjugated nanostructures at the atomic level. Herein we demonstrate a selective on-surface covalent coupling reaction that is templated by metal-organic coordinative bonding, and achieve a porous nitrogen-doped carbon nanoribbon structure. In contrast to the inhomogeneous polymorphic structures resulting from the debrominated aryl-aryl coupling reaction on Au(111), the incorporation of an Fe-terpyridine (tpy) coordination motif into the on-surface reaction controls the molecular conformation, guides the reaction pathway, and finally yields pure organic sexipyridine-p-phenylene nanoribbons. Emergent molecular conformers and reaction products in the reaction pathways are revealed by scanning tunneling microscopy, density functional theory calculations and X-ray photoelectron spectroscopy, demonstrating the template effect of Fe-tpy coordination on the on-surface covalent coupling. Our approach opens an avenue for the rational design and synthesis of functional conjugated nanomaterials with atomic precision.
控制表面反应途径对于在原子水平上精确构建共轭纳米结构至关重要，但具有挑战性。在此，我们展示了一种受金属-有机配位键模板化的选择性表面共价偶联反应，并实现了多孔氮掺杂碳纳米带结构。与在 Au(111)上发生的脱溴芳基-芳基偶联反应导致的不均匀多晶型结构相反，将 Fe-三联吡啶 (tpy) 配位基序引入表面反应中控制了分子构象，引导了反应途径，最终得到纯有机六吡啶-对亚苯基纳米带。通过扫描隧道显微镜、密度泛函理论计算和 X 射线光电子能谱揭示了反应途径中出现的分子构象和反应产物，证明了 Fe-tpy 配位对表面共价偶联的模板效应。我们的方法为具有原子精度的功能共轭纳米材料的合理设计和合成开辟了道路。
