Quantum interference enhanced thermopower in single-molecule thiophene junctions  

作　　者：Hang Chen Yaorong Chen Hewei Zhang Wenqiang Cao Chao Fang Yicheng Zhou Zongyuan Xiao Jia Shi Wenbo Chen Junyang Liu Wenjing Hong 

机构地区：[1]State Key Laboratory of Physical Chemistry of Solid Surfaces,iChEM,College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,China [2]Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power,Shanghai University of Electric Power,Shanghai 200090,China [3]Beijing National Laboratory for Molecular Sciences,Beijing 100190,China

出　　处：《Chinese Chemical Letters》2022年第1期523-526,共4页中国化学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.21722305,21933012,31871877);the National Key R&D Program of China(No.2017YFA0204902);the Fundamental Research Funds for the Central Universities(Nos.20720200068,20720190002);the Natural Science Foundation of Shanghai(No.20ZR1471600);the Science and Technology Commission of Shanghai Municipality(No.19DZ2271100);Natural Science Foundation of Fujian Province(No.2018J06004);the Beijing National Laboratory for Molecular Sciences(No.BNLMS202005)。

摘　　要：Quantum interference(QI)effects,which offer unique opportunities to widely manipulate the charge transport properties in the molecular junctions,will have the potential for achieving high thermopower.Here we developed a scanning tunneling microscope break junction technique to investigate the thermopower through single-molecule thiophene junctions.We observed that the thermopower of 2,4-TPSAc with destructive quantum interference(DQI)was nearly twice of 2,5-TP-SAc without DQI,while the conductance of the 2,4-TP-SAc was two orders of magnitude lower than that of 2,5-TP-SAc.Furthermore,we found the thermopower was almost the same by altering the anchoring group or thiophene core in the control experiments,suggesting that the QI effect is responsible for the increase of thermopower.The density functional theory(DFT)calculations are in quantitative agreement with the experimental data.Our results reveal that QI effects can provide a promising platform to enhance the thermopower of molecular junctions.

关 键 词：Quantum interference THERMOPOWER Thermoelectric device Single-molecule electronics Single-molecule junctions 

分 类 号：O626.12[理学—有机化学] O641[理学—化学]