Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Chem Commun (Camb). 2023 May 18;59(41):6207-6210. doi: 10.1039/d3cc01113e.
Covalent metal-carbon (M-C) contacts have long been pursued for constructing robust and high-performance molecular devices. Existing methods for creating such contacts usually rely on direct chemical reactions between metal electrodes and designed molecular ligands. An inherent limitation of this approach is that the commonly used metal electrodes (, Au) are chemically inert, making it generally difficult to form covalent M-C bonds with molecules. Intriguingly, employing the scanning tunneling microscope-break junction technique, we find that simply adding Ag ions to molecular solution enables direct covalent bonding of terminal alkynes to Au electrodes. The bonding process is driven by Ag ion coupled reactions and efficiently creates covalent Au/Ag-C interfaces in single molecule junctions. This metal ion assisted method avoids the need for complex synthesis of molecular ligands and works robustly for a wide range of alkyne-terminated molecules, offering a facile and versatile approach for precisely tuning the metal-molecule interface.
共价金属-碳 (M-C) 键一直以来都被用于构建稳健且高性能的分子器件。目前构建此类键的方法通常依赖于金属电极与设计好的分子配体之间的直接化学反应。这种方法的一个固有局限性是，常用的金属电极（如 Au）化学惰性较强，因此通常难以与分子形成共价 M-C 键。有趣的是，我们通过扫描隧道显微镜-断键技术发现，只需在分子溶液中添加 Ag 离子，就可以使末端炔烃与 Au 电极直接形成共价键。该键合过程由 Ag 离子偶联反应驱动，可在单分子结中有效地形成共价 Au/Ag-C 界面。这种金属离子辅助的方法避免了复杂的分子配体合成，并且对各种末端炔烃分子都具有强大的稳定性，为精确调整金属-分子界面提供了一种简单且通用的方法。
