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.
Recently, Prof. Jian Fan from FUNSOM, Prof. Ziliang Shi and Prof. Yuqiang Ma from Center for Soft Condensed Matter Physics and Interdisciplinary Research and School of Physical Science and Technology, and Prof. Hu Xu fromSouthern University of Science and Technology have effectively combined the two independent research fields of surface supramolecular self-assembly and surface covalent reaction, which provides a new idea for constructing complex surface functional organic nanostructures in the future. Their work has been published in Nature Communications (Nat. Commun., 2019, 10, 70), titled as Selective On-Surface Covalent Coupling Based on Metal-Organic Coordination Template.
This work will have a long-term impact on the rapid-developing research field of surface covalent synthesis.
Link to Paper: https://www.nature.com/articles/s41467-018-07933-0
Editor: Danting Xiang