Wakizaka Masanori, Kumagai Shohei, Wu Hashen, Sonobe Takuya, Iguchi Hiroaki, Yoshida Takefumi, Yamashita Masahiro, Takaishi Shinya
Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Aoba-Ku, Sendai, 980-8578, Japan.
School of Materials Science and Engineering, Nankai University, Tianjin, 300350, PR China.
Nat Commun. 2022 Mar 4;13(1):1188. doi: 10.1038/s41467-022-28875-8.
The creation of low-dimensional heterostructures for intelligent devices is a challenging research topic; however, macro- and atomic-scale connections in one-dimensional (1D) electronic systems have not been achieved yet. Herein, we synthesize a heterostructure comprising a 1D Mott insulator [Ni(chxn)Br]Br (1; chxn = 1R-2R-diaminocyclohexane) and a 1D Peierls or charge-density-wave insulator [Pd(chxn)Br]Br (2) using stepwise electrochemical growth. It can be considered as the first example of electrochemical liquid-phase epitaxy applied to molecular-based heterostructures with a macroscopic scale. Moreover, atomic-resolution scanning tunneling microscopy images reveal a modulation of the electronic state in the heterojunction region with a length of five metal atoms (~ 2.5 nm), that is a direct evidence for the atomic-scale connection of 1 and 2. This is the first time that the heterojunction in the 1D chains has been shown and examined experimentally at macro- and atomic-scale. This study thus serves as proof of concept for heterojunctions in 1D electronic systems.
用于智能设备的低维异质结构的创建是一个具有挑战性的研究课题；然而，一维（1D）电子系统中的宏观和原子尺度连接尚未实现。在此，我们使用逐步电化学生长法合成了一种异质结构，该异质结构由一维莫特绝缘体[Ni(chxn)Br]Br（1；chxn = 1R - 2R - 二氨基环己烷）和一维派尔斯或电荷密度波绝缘体[Pd(chxn)Br]Br（2）组成。它可被视为应用于宏观尺度分子基异质结构的电化学液相外延的首个实例。此外，原子分辨率扫描隧道显微镜图像揭示了在长度为五个金属原子（约2.5纳米）的异质结区域中电子态的调制，这是1和2原子尺度连接的直接证据。这是首次在宏观和原子尺度上展示并通过实验研究一维链中的异质结。因此，本研究为一维电子系统中的异质结提供了概念验证。
