Zhang Yong, Lu Jianchen, Li Yang, Li Baijin, Ruan Zilin, Zhang Hui, Hao Zhenliang, Sun Shijie, Xiong Wei, Gao Lei, Chen Long, Cai Jinming
Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China.
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, China.
Angew Chem Int Ed Engl. 2022 Jul 11;61(28):e202204736. doi: 10.1002/anie.202204736. Epub 2022 May 17.
Doped graphene nanoribbons (GNRs) with heteroatoms are a principal strategy to fine-tune the electronic structures of GNRs for future device applications. Here, we successfully synthesized the N=9 nitrogen-doped armchair GNR on the Au(111) surface. Due to the flexibility of precursor molecules, three different covalent bonds (C-C, C-N, N-N) are formed in the GNR backbone. Scanning tunneling spectroscopy analysis together with band structure calculations reveals that the band gap of the N-9-AGNRs (C-C) will be enlarged compared to pristine 9-AGNRs, and the C-N bond and N-N bond at the isolated site of N-9-AGNR (C-C) will introduce new defect states near the Fermi level. DFT calculations reveal that the electronic structure of N-9-AGNR (C-C) shows semiconductor character, while N-9-AGNR (C-N) and N-9-AGNR (N-N) display metallic character. Our results provide a promising route for creating more complex molecular heterostructures with tunable band gaps, which may be useful for future molecular electronics and memory device applications.
掺杂有杂原子的石墨烯纳米带（GNRs）是微调GNRs电子结构以用于未来器件应用的主要策略。在此，我们成功地在Au(111)表面合成了N = 9的氮掺杂扶手椅型GNR。由于前驱体分子的灵活性，在GNR主链中形成了三种不同的共价键（C - C、C - N、N - N）。扫描隧道光谱分析以及能带结构计算表明，与原始的9 - AGNRs相比，N - 9 - AGNRs（C - C）的带隙将增大，并且在N - 9 - AGNR（C - C）的孤立位点处的C - N键和N - N键将在费米能级附近引入新的缺陷态。密度泛函理论计算表明，N - 9 - AGNR（C - C）的电子结构显示出半导体特性，而N - 9 - AGNR（C - N）和N - 9 - AGNR（N - N）表现出金属特性。我们的结果为创建具有可调带隙的更复杂分子异质结构提供了一条有前景的途径，这可能对未来的分子电子学和存储器件应用有用。
