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稳定光开关单分子结中可调谐对称性破缺诱导双功能
作者:小柯机器人 发布时间:2021/12/4 11:40:01

北京大学郭雪峰团队开发了稳定光开关单分子结中可调谐对称性破缺诱导双功能的策略。相关研究成果发表在2021年11月30日出版的《美国化学会杂志》。

分子电子学的目标是使有源电子器件小型化,并最终利用具有各种功能的不同结构的分子构建单分子纳米电路,这是一项极具挑战性的任务。

该文中,研究人员在一个初始对称的单分子光开关中同时实现了门控整流功能(开/关比达到~60)和高性能场效应(最大开/关比>100),该光开关包含一个夹在石墨烯电极之间的共价双核钌二芳基乙烯(Ru DAE)复合物。实验和理论结果一致表明,在开环Ru-DAE分子中,位于每个Ru碎片上的初始退化前沿分子轨道可以分别调谐,并在栅极电场下不对称移动。该对称轨道移动(AOS)提高了简并度并破坏了分子的对称性,不仅实现具有可调整流比和受控极性的类二极管行为的必要条件,而且还增强了整流方向的场效应开/关比。此外,该门控对称性破缺效应可以通过在光刺激下使DAE单元在其开环和闭环形式之间异构化来打开/关闭。

该新方案为构建高性能多功能分子纳米电路提供了一种通用而有效的策略。

附:英文原文

Title: Tunable Symmetry-Breaking-Induced Dual Functions in Stable and Photoswitched Single-Molecule Junctions

Author: Na Xin, Chen Hu, Hassan Al Sabea, Miao Zhang, Chenguang Zhou, Linan Meng, Chuancheng Jia, Yao Gong, Yu Li, Guojun Ke, Xiaoyan He, Pramila Selvanathan, Lucie Norel, Mark A. Ratner, Zhirong Liu, Shengxiong Xiao, Stéphane Rigaut, Hong Guo, Xuefeng Guo

Issue&Volume: November 30, 2021

Abstract: The aim of molecular electronics is to miniaturize active electronic devices and ultimately construct single-molecule nanocircuits using molecules with diverse structures featuring various functions, which is extremely challenging. Here, we realize a gate-controlled rectifying function (the on/off ratio reaches ~60) and a high-performance field effect (maximum on/off ratio >100) simultaneously in an initially symmetric single-molecule photoswitch comprising a dinuclear ruthenium-diarylethene (Ru-DAE) complex sandwiched covalently between graphene electrodes. Both experimental and theoretical results consistently demonstrate that the initially degenerated frontier molecular orbitals localized at each Ru fragment in the open-ring Ru-DAE molecule can be tuned separately and shift asymmetrically under gate electric fields. This symmetric orbital shifting (AOS) lifts the degeneracy and breaks the molecular symmetry, which is not only essential to achieve a diode-like behavior with tunable rectification ratio and controlled polarity, but also enhances the field-effect on/off ratio at the rectification direction. In addition, this gate-controlled symmetry-breaking effect can be switched on/off by isomerizing the DAE unit between its open-ring and closed-ring forms with light stimulus. This new scheme offers a general and efficient strategy to build high-performance multifunctional molecular nanocircuits.

DOI: 10.1021/jacs.1c08997

Source: https://pubs.acs.org/doi/10.1021/jacs.1c08997

 

期刊信息

JACS:《美国化学会志》,创刊于1879年。隶属于美国化学会,最新IF:14.612
官方网址:https://pubs.acs.org/journal/jacsat
投稿链接:https://acsparagonplus.acs.org/psweb/loginForm?code=1000