Zeng Biao-Feng, Wang Gan, Qian Qiao-Zan, Chen Zhi-Xin, Zhang Xia-Guang, Lu Zhi-Xing, Zhao Shi-Qiang, Feng An-Ni, Shi Jia, Yang Yang, Hong Wenjing
Pen-Tung Sah Institute of Micro-Nano Science and Technology, College of Chemistry and Chemical Engineering and State Key Laboratory of Physical Chemistry of Solid Surfaces, IKKEM, iChEM, Xiamen University, Xiamen, 361005, China.
School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, China.
Small. 2020 Dec;16(48):e2004720. doi: 10.1002/smll.202004720. Epub 2020 Nov 5.
Recent progress in addressing electrically driven single-molecule behaviors has opened up a path toward the controllable fabrication of molecular devices. Herein, the selective fabrication of single-molecule junctions is achieved by employing the external electric field. For molecular junctions with methylthio (-SMe), thioacetate (-SAc), amine (-NH ), and pyridyl (-PY), the evolution of their formation probabilities along with the electric field is extracted from the plateau analysis of individual single-molecule break junction traces. With the increase of the electric field, the SMe-anchored molecules show a different trend in the formation probability compared to the other molecular junctions, which is consistent with the density functional theory calculations. Furthermore, switching from an SMe-anchored junction to an SAc-anchored junction is realized by altering the electric field in a mixed solution. The results in this work provide a new approach to the controllable fabrication and modulation of single-molecule junctions and other bottom-up nanodevices at molecular scales.
在解决电驱动单分子行为方面的最新进展为分子器件的可控制造开辟了一条道路。在此，通过施加外部电场实现了单分子结的选择性制造。对于具有甲硫基（-SMe）、硫代乙酸酯（-SAc）、胺（-NH ）和吡啶基（-PY）的分子结，从单个单分子断结迹线的平台分析中提取了它们的形成概率随电场的演变。随着电场的增加，与其他分子结相比，以SMe为锚定基团的分子在形成概率上呈现出不同的趋势，这与密度泛函理论计算结果一致。此外，通过在混合溶液中改变电场，实现了从以SMe为锚定基团的结到以SAc为锚定基团的结的转换。这项工作的结果为在分子尺度上可控制造和调制单分子结及其他自下而上的纳米器件提供了一种新方法。
