Theoretical Design of Molecular Diode Based on Thiol-and Amino-Terminated Molecules  

基于硫醇与氨基的分子二极管的理论设计

作　　者：Xiaolong Yue Min Zou Xianfei Di Ziqin Wang Wei Hu 岳晓龙;邹敏;邸纤斐;王梓钦;胡伟(齐鲁工业大学(山东省科学院)化学与化工学院,济南250353)

机构地区：[1]School of Chemistry and Chemical Engineering,Qilu University of Technology(Shandong Academy of Sciences),Jinan250353,China

出　　处：《Chinese Journal of Chemical Physics》2024年第5期638-643,I0063-I0065,I0100,共10页化学物理学报（英文）

基　　金：This work was supported by the National Natural Science Foundation of China(No.22073053);the Young Taishan Scholar Program of Shandong Province(No.tsqn201909139);the Program for Scientific Research Innovation Team in Colleges and Universities of Jinan(No.2021GXRC042);the Program for Introduced Innovation Teams from the New Collegiate 20 Items of Jinan(No.202228031);the Natural Science Foundation of Shandong Province(No.ZR2023MA089);Qilu University of Technology(Shandong Academy of Sciences)Basic Research Project of Science,Education and Industry Integration Pilot(No.2023PY046).

摘　　要：Utilizing density functional theory(DFT)and non-equilibrium Green's function,we systematically studied the electrical transport and rectification properties of thiol-and amino-terminated molecules embedded in graphene nanoribbons.We firstly found the thiol-terminated moleculesshowbetterelectron transport properties compared to the amino-terminated,which can be attributed to the strong electronwithdrawing ability and favorable coupling effects.Secondly,the symmetrical molecules show almost symmetrical current-voltage(-V)curves and exhibit negligible rectification effects.On the other hand,the asymmetrical molecules exhibit asymmetrical I-V curves and better rectification performance.The rectification effect is closely related to molecular asymmetry degrees.For example,the rectification ratio of asymmetric N6((E)-N1-(3-aminopropyl)-but-2-ene-1,4-diamine)molecule is much smaller than the N4(5-phenylthiazole-2,4-diamine)and N5(2,6-diaminohexane-1,1,5-triol)molecules.Furthermore,we found the rectification ratio of the asymmetrical amino-terminated molecules can reach 400,while the biggest rectification ratio of the thiol-terminated molecule can only reach 45.These findings offer crucial insights for future graphene molecular electronic device design.本文利用密度泛函理论和非平衡格林函数方法,系统地研究了基于石墨烯纳米带的硫醇和氨基的分子器件的电输运和整流特性:首先,我们发现了硫醇端基分子相比氨基端基分子表现出更好的电子输运性能,这归因于强电子吸引能力和强耦合效应。其次,对称分子结构呈现出对称的电压-电流曲线,导致整流效应忽略不计.然而,不对称的分子结构呈现出不对称的电压-电流曲线,从而具备了更好的整流性能.因此,整流效应与分子的不对称程度密切相关.例如,由于左侧和右侧存在相似的化学官能团,不对称分子N6((E)-N1-(3-氮基丙基)-2-丁烯-1,4-二胺)的整流比远小于不对称分子N4(5-苯基噻唑-2,4-二胺)和N5(2,6-二氨基-1,1,5-己三醇).此外,不对称氨基端基分子的整流比高达400,而硫醇端基分子的最大整流比仅为45.本研究为石墨烯分子电子器件的设计提供了有力的理论支持.

关 键 词：GRAPHENE Molecular junction Electron transport 

分 类 号：O62[理学—有机化学]