电化学门控调节具有平行路径的单分子电路中电子传输  

Electrochemical Gating Single-Molecule Circuits with Parallel Paths

作　　者：苏俊青 周一帆 童凌 王亚浩 郑菊芳 陈竞哲 周小顺 Jun-Qing Su;Yi-Fan Zhou;Ling Tong;Ya-Hao Wang;Ju-Fang Zheng;Jing-Zhe Chen;Xiao-Shun Zhou(Key Laboratory of the Ministry of Education for Advanced Catalysis Materials,Institute of Physical Chemistry,Zhejiang Normal University,Jinhua 321004,Zhejiang,China;Department of Physics,Shanghai University,Shanghai 200444,China)

机构地区：[1]浙江师范大学物理化学研究所,先进催化材料教育部重点实验室,浙江金华321004 [2]上海大学物理系,上海200444

出　　处：《电化学》2021年第2期195-201,共7页Journal of Electrochemistry

基　　金：Financial support from the National Natural Science Foundation of China(No.21872126);the Zhejiang Provincial Natural Science Foundation of China(No.LQ21B030010)。

摘　　要：电化学门控已成为一种可行且高效调节单分子电导的方法。在本研究中,我们证实了具有两个平行苯环的单分子电路中电子传输可以通过电化学门控控制。首先,我们利用STM-BJ技术以金为电极构筑了具有两条平行路径的单分子结。与单条路径的单分子结相比,两条路径的分子结由于具有增强性量子干涉效应,具有2.82倍的电导值。进一步地,我们利用电化学门控对具有两个平行苯环的单分结的电导进行调控,获得了333%·V^(-1)调节比。结合DFT计算,发现在E=E_F附近的V形透射系数谱图导致了实验观测的电导门控行为。本研究揭示了具有平行路径的单分子电路的电化学门控行为,并为设计高性能分子器件的分子材料提供了新的途径。Electrochemical gating has emerged as a feasible and powerful method to tune single-molecule conductance.Herein,we demonstrate that the electron transport through single-molecule circuits with two benzene rings in parallel could be efficiently gated by electrochemistry.The molecular junctions with two parallel paths are fabricated with Au electrodes by STM break junction(STM-BJ)technique.Their conductance value exhibits a 2.82-fold enhancement by the constructive quantum interference compared to single-molecule junctions with single path for electron tunneling.Furthermore,the conductance of para-benzene based molecule could be electrochemically tuned with a modulation ratio of about 333%·V^(-1).With the help of DFT calculations,a V-shape spectra of energy-dependent transmission coefficients T(E)around E=EF leads to the conductance gating behavior.The current work sheds a light on the electrochemical gating of single-molecule circuits with parallel paths,and offers a new way to design molecular materials for a high-performance molecular device.

关 键 词：分子结 电化学门控 分子结构 ECSTM-BJ 增强性量子干涉 

分 类 号：O646[理学—物理化学]