CIC nanoGUNE , Tolosa Hiribidea 76, 20018 Donostia-San Sebastian, Spain.
Centro de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela , 15782 Santiago de Compostela, Spain.
ACS Nano. 2017 Jul 25;11(7):7355-7361. doi: 10.1021/acsnano.7b03522. Epub 2017 Jul 3.
We report the on-surface synthesis of 7-armchair graphene nanoribbons (7-AGNRs) substituted with nitrile (CN) functional groups. The CN groups are attached to the GNR backbone by modifying the 7-AGNR precursor. Whereas many of these groups survive the on-surface synthesis, the reaction process causes the cleavage of some CN from the ribbon backbone and the on-surface cycloisomerization of few nitriles onto pyridine rings. Scanning tunneling spectroscopy and density functional theory reveal that CN groups behave as very efficient n-dopants, significantly downshifting the bands of the ribbon and introducing deep impurity levels associated with the nitrogen electron lone pairs.
我们报告了通过在表面合成带有氰基（CN）官能团的 7-扶手椅型石墨烯纳米带（7-AGNRs）。CN 基团通过修饰 7-AGNR 前体连接到 GNR 主链上。尽管这些基团中的许多基团在表面合成过程中得以保留，但反应过程导致一些 CN 从 ribbons 主链上断裂，以及少数腈基在表面环异构化成吡啶环。扫描隧道谱和密度泛函理论揭示，CN 基团表现出非常有效的 n 型掺杂剂的性质，显著下转换了 ribbon 的能带，并引入了与氮电子孤对相关的深杂质能级。
