Influence of Molecular Structure on Contact Interaction between Thiophene Anchoring Group and Au Electrode

作者：Jin-Chuan Mao, Lin-Lu Peng, Wei‐Qiong Li, Fang Chen, Huigang Wang, Yong Shao, Xiao‐Shun Zhou, Xueqin Zhao, Hujun Xie, Zhen‐Jiang Niu · 发表于：The Journal of Physical Chemistry C · 年份：2017 · DOI：10.1021/acs.jpcc.6b10925 · 被引用次数：20 · 研究领域：Molecular Junctions and Nanostructures、Nanowire Synthesis and Applications、Electrochemical Analysis and Applications

In this Article, the single molecular junctions of thiophene-based molecules are measured by scanning tunneling microscopy break junction (STM-BJ) in ambient air. While the benzo[1,2- b:4,5- b ′]dithiophene ( 1 ) and 2,6-dibromobenzo[1,2- b:4,5- b ′]dithiophene ( 2 ) give out histograms with well-defined peaks corresponding to the molecular junction, thieno[3,2- b ]thiophene ( 3 ) does not show a peak for the molecular junction. The disappearance of peak may contribute to the weak interaction between thiophene and Au. DFT calculation results demonstrate the weak interaction for 3 contacting Au as compared to 1 and 2 . Interestingly, the step probability for molecular junction follows the order of binding interaction between thiophene and Au showing 1 > 2 > 3 . The current results reveal the influence of molecular structure on contact interaction between anchoring group and electrode, which can help to understand the electron transport of the single molecular junction.