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Zhang W, Zhao Z, Tan M, Adijiang A, Zhong S, Xu X, Zhao T, Ramya E, Sun L, Zhao X, Fan Z, Xiang D. Regulating the orientation of a single coordinate bond by the synergistic action of mechanical forces and electric field. Chem Sci 2023; 14:11456-11465. [PMID: 37886107 PMCID: PMC10599463 DOI: 10.1039/d3sc03892k] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 09/30/2023] [Indexed: 10/28/2023] Open
Abstract
The molecular binding orientation with respect to the electrode plays a pivotal role in determining the performance of molecular devices. However, accomplishing in situ modulation of single-molecule binding orientation remains a great challenge due to the lack of suitable testing systems and characterization approaches. To this end, by employing a developed STM-BJ technique, we demonstrate that the conductance of pyridine-anchored molecular junctions decreases as the applied voltage increases, which is determined by the repeated formation of thousands of gold-molecule-gold dynamic break junctions. In contrast, the static fixed molecular junctions (the distance between two electrodes is fixed) with identical molecules exhibit a reverse tendency as the bias voltage increases. Supported by flicker noise measurements and theoretical calculations, we provide compelling evidence that the orientation of nitrogen-gold bonds (a universal coordinate bond) in the pyridine-anchored molecular junctions can be manipulated to align with the electric field by the synergistic action of the mechanical stretching force and the electric fields, whereas either stimulus alone cannot achieve the same effect. Our study provides a framework for characterizing and regulating the orientation of a single coordinate bond, offering an approach to control electron transport through single molecular junctions.
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Affiliation(s)
- Wei Zhang
- Institute of Modern Optics, Center of Single Molecule Sciences, Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University Tianjin 300350 China
| | - Zhibin Zhao
- Institute of Modern Optics, Center of Single Molecule Sciences, Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University Tianjin 300350 China
| | - Min Tan
- Institute of Modern Optics, Center of Single Molecule Sciences, Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University Tianjin 300350 China
| | - Adila Adijiang
- Institute of Modern Optics, Center of Single Molecule Sciences, Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University Tianjin 300350 China
| | - Shurong Zhong
- Institute of Modern Optics, Center of Single Molecule Sciences, Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University Tianjin 300350 China
| | - Xiaona Xu
- Institute of Modern Optics, Center of Single Molecule Sciences, Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University Tianjin 300350 China
| | - Tianran Zhao
- Institute of Modern Optics, Center of Single Molecule Sciences, Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University Tianjin 300350 China
| | - Emusani Ramya
- Institute of Modern Optics, Center of Single Molecule Sciences, Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University Tianjin 300350 China
| | - Lu Sun
- Institute of Modern Optics, Center of Single Molecule Sciences, Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University Tianjin 300350 China
| | - Xueyan Zhao
- Institute of Modern Optics, Center of Single Molecule Sciences, Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University Tianjin 300350 China
| | - Zhiqiang Fan
- School of Physics and Electronic Science, Changsha University of Science and Technology Changsha 410114 China
| | - Dong Xiang
- Institute of Modern Optics, Center of Single Molecule Sciences, Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University Tianjin 300350 China
- School of Materials Science and Engineering, Smart Sensing Interdisciplinary Science Center, Nankai University Tianjin 300350 China
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2
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Li T, Bandari VK, Schmidt OG. Molecular Electronics: Creating and Bridging Molecular Junctions and Promoting Its Commercialization. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2209088. [PMID: 36512432 DOI: 10.1002/adma.202209088] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 11/28/2022] [Indexed: 06/02/2023]
Abstract
Molecular electronics is driven by the dream of expanding Moore's law to the molecular level for next-generation electronics through incorporating individual or ensemble molecules into electronic circuits. For nearly 50 years, numerous efforts have been made to explore the intrinsic properties of molecules and develop diverse fascinating molecular electronic devices with the desired functionalities. The flourishing of molecular electronics is inseparable from the development of various elegant methodologies for creating nanogap electrodes and bridging the nanogap with molecules. This review first focuses on the techniques for making lateral and vertical nanogap electrodes by breaking, narrowing, and fixed modes, and highlights their capabilities, applications, merits, and shortcomings. After summarizing the approaches of growing single molecules or molecular layers on the electrodes, the methods of constructing a complete molecular circuit are comprehensively grouped into three categories: 1) directly bridging one-molecule-electrode component with another electrode, 2) physically bridging two-molecule-electrode components, and 3) chemically bridging two-molecule-electrode components. Finally, the current state of molecular circuit integration and commercialization is discussed and perspectives are provided, hoping to encourage the community to accelerate the realization of fully scalable molecular electronics for a new era of integrated microsystems and applications.
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Affiliation(s)
- Tianming Li
- Research Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09111, Chemnitz, Germany
| | - Vineeth Kumar Bandari
- Research Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09111, Chemnitz, Germany
| | - Oliver G Schmidt
- Research Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09111, Chemnitz, Germany
- Nanophysics, Dresden University of Technology, 01069, Dresden, Germany
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3
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Dief EM, Low PJ, Díez-Pérez I, Darwish N. Advances in single-molecule junctions as tools for chemical and biochemical analysis. Nat Chem 2023; 15:600-614. [PMID: 37106094 DOI: 10.1038/s41557-023-01178-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 03/02/2023] [Indexed: 04/29/2023]
Abstract
The development of miniaturized electronics has led to the design and construction of powerful experimental platforms capable of measuring electronic properties to the level of single molecules, along with new theoretical concepts to aid in the interpretation of the data. A new area of activity is now emerging concerned with repurposing the tools of molecular electronics for applications in chemical and biological analysis. Single-molecule junction techniques, such as the scanning tunnelling microscope break junction and related single-molecule circuit approaches have a remarkable capacity to transduce chemical information from individual molecules, sampled in real time, to electrical signals. In this Review, we discuss single-molecule junction approaches as emerging analytical tools for the chemical and biological sciences. We demonstrate how these analytical techniques are being extended to systems capable of probing chemical reaction mechanisms. We also examine how molecular junctions enable the detection of RNA, DNA, and traces of proteins in solution with limits of detection at the zeptomole level.
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Affiliation(s)
- Essam M Dief
- School of Molecular and Life Sciences, Curtin University, Bentley, Western Australia, Australia
| | - Paul J Low
- School of Molecular Sciences, University of Western Australia, Crawley, Western Australia, Australia
| | - Ismael Díez-Pérez
- Department of Chemistry, Faculty of Natural & Mathematical Sciences, King's College London, London, UK
| | - Nadim Darwish
- School of Molecular and Life Sciences, Curtin University, Bentley, Western Australia, Australia.
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4
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Zhao X, Zhang X, Yin K, Zhang S, Zhao Z, Tan M, Xu X, Zhao Z, Wang M, Xu B, Lee T, Scheer E, Xiang D. In Situ Adjustable Nanogaps and In-Plane Break Junctions. SMALL METHODS 2023; 7:e2201427. [PMID: 36732898 DOI: 10.1002/smtd.202201427] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/27/2022] [Indexed: 06/18/2023]
Abstract
The ability to precisely regulate the size of a nanogap is essential for establishing high-yield molecular junctions, and it is crucial for the control of optical signals in extreme optics. Although remarkable strategies for the fabrication of nanogaps are proposed, wafer-compatible nanogaps with freely adjustable gap sizes are not yet available. Herein, two approaches for constructing in situ adjustable metal gaps are proposed which allow Ångstrom modulation resolution by employing either a lateral expandable piezoelectric sheet or a stretchable membrane. These in situ adjustable nanogaps are further developed into in-plane molecular break junctions, in which the gaps can be repeatedly closed and opened thousands of times with self-assembled molecules. The conductance of the single 1,4-benzenediamine (BDA) and the BDA molecular dimer is successfully determined using the proposed strategy. The measured conductance agreeing well with the data by employing another well-established scanning tunneling microscopy break junction technique provides insight into the formation of molecule dimer via hydrogen bond at single molecule level. The wafer-compatible nanogaps and in-plane dynamical break-junctions provide a potential approach to fabricate highly compacted devices using a single molecule as a building block and supply a promising in-plane technique to address the dynamical properties of single molecules.
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Affiliation(s)
- Xueyan Zhao
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin, 300350, China
| | - Xubin Zhang
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin, 300350, China
| | - Kaikai Yin
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin, 300350, China
| | - Surong Zhang
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin, 300350, China
| | - Zhikai Zhao
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin, 300350, China
| | - Min Tan
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin, 300350, China
| | - Xiaona Xu
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin, 300350, China
| | - Zhibin Zhao
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin, 300350, China
| | - Maoning Wang
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin, 300350, China
| | - Bingqian Xu
- College of Engineering, University of Georgia, Athens, GA, 30602, USA
| | - Takhee Lee
- Department of Physics and Astronomy, and Institute of Applied Physics, Seoul National University, Seoul, 08826, Korea
| | - Elke Scheer
- Department of Physics, University of Konstanz, 78457, Konstanz, Germany
| | - Dong Xiang
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin, 300350, China
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5
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Plasmonic phenomena in molecular junctions: principles and applications. Nat Rev Chem 2022; 6:681-704. [PMID: 37117494 DOI: 10.1038/s41570-022-00423-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2022] [Indexed: 11/08/2022]
Abstract
Molecular junctions are building blocks for constructing future nanoelectronic devices that enable the investigation of a broad range of electronic transport properties within nanoscale regions. Crossing both the nanoscopic and mesoscopic length scales, plasmonics lies at the intersection of the macroscopic photonics and nanoelectronics, owing to their capability of confining light to dimensions far below the diffraction limit. Research activities on plasmonic phenomena in molecular electronics started around 2010, and feedback between plasmons and molecular junctions has increased over the past years. These efforts can provide new insights into the near-field interaction and the corresponding tunability in properties, as well as resultant plasmon-based molecular devices. This Review presents the latest advancements of plasmonic resonances in molecular junctions and details the progress in plasmon excitation and plasmon coupling. We also highlight emerging experimental approaches to unravel the mechanisms behind the various types of light-matter interactions at molecular length scales, where quantum effects come into play. Finally, we discuss the potential of these plasmonic-electronic hybrid systems across various future applications, including sensing, photocatalysis, molecular trapping and active control of molecular switches.
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6
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Light-Driven Charge Transport and Optical Sensing in Molecular Junctions. NANOMATERIALS 2022; 12:nano12040698. [PMID: 35215024 PMCID: PMC8878161 DOI: 10.3390/nano12040698] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/15/2022] [Accepted: 02/17/2022] [Indexed: 12/11/2022]
Abstract
Probing charge and energy transport in molecular junctions (MJs) has not only enabled a fundamental understanding of quantum transport at the atomic and molecular scale, but it also holds significant promise for the development of molecular-scale electronic devices. Recent years have witnessed a rapidly growing interest in understanding light-matter interactions in illuminated MJs. These studies have profoundly deepened our knowledge of the structure–property relations of various molecular materials and paved critical pathways towards utilizing single molecules in future optoelectronics applications. In this article, we survey recent progress in investigating light-driven charge transport in MJs, including junctions composed of a single molecule and self-assembled monolayers (SAMs) of molecules, and new opportunities in optical sensing at the single-molecule level. We focus our attention on describing the experimental design, key phenomena, and the underlying mechanisms. Specifically, topics presented include light-assisted charge transport, photoswitch, and photoemission in MJs. Emerging Raman sensing in MJs is also discussed. Finally, outstanding challenges are explored, and future perspectives in the field are provided.
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7
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Charge Transport Characteristics of Molecular Electronic Junctions Studied by Transition Voltage Spectroscopy. MATERIALS 2022; 15:ma15030774. [PMID: 35160719 PMCID: PMC8836750 DOI: 10.3390/ma15030774] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 01/11/2022] [Accepted: 01/18/2022] [Indexed: 11/25/2022]
Abstract
The field of molecular electronics is prompted by tremendous opportunities for using a single-molecule and molecular monolayers as active components in integrated circuits. Until now, a wide range of molecular devices exhibiting characteristic functions, such as diodes, transistors, switches, and memory, have been demonstrated. However, a full understanding of the crucial factors that affect charge transport through molecular electronic junctions should yet be accomplished. Remarkably, recent advances in transition voltage spectroscopy (TVS) elucidate that it can provide key quantities for probing the transport characteristics of the junctions, including, for example, the position of the frontier molecular orbital energy relative to the electrode Fermi level and the strength of the molecule–electrode interactions. These parameters are known to be highly associated with charge transport behaviors in molecular systems and can then be used in the design of molecule-based devices with rationally tuned electronic properties. This article highlights the fundamental principle of TVS and then demonstrates its major applications to study the charge transport properties of molecular electronic junctions.
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8
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Fukuzumi R, Buerkle M, Li Y, Kaneko S, Li P, Kobayashi S, Fujii S, Kiguchi M, Nakamura H, Tsukagoshi K, Nishino T. Water Splitting Induced by Visible Light at a Copper-Based Single-Molecule Junction. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2008109. [PMID: 34089231 DOI: 10.1002/smll.202008109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 04/19/2021] [Indexed: 06/12/2023]
Abstract
Water splitting is an essential process for converting light energy into easily storable energy in the form of hydrogen. As environmentally preferable catalysts, Cu-based materials have attracted attention as water-splitting catalysts. To enhance the efficiency of water splitting, a reaction process should be developed. Single-molecule junctions (SMJs) are attractive structures for developing these reactions because the molecule electronic state is significantly modulated, and characteristic electromagnetic effects can be expected. Here, water splitting is induced at Cu-based SMJ and the produced hydrogen is characterized at a single-molecule scale by employing electron transport measurements. After visible light irradiation, the conductance states originate from Cu/hydrogen molecule/Cu junctions, while before irradiation, only Cu/water molecule/Cu junctions were observed. The vibration spectra obtained from inelastic electron tunneling spectroscopy combined with the first-principles calculations reveal that the water molecule trapped between the Cu electrodes is decomposed and that hydrogen is produced. Time-dependent and wavelength-dependent measurements show that localized-surface plasmon decomposes the water molecule in the vicinity of the junction. These findings indicate the potential ability of Cu-based materials for photocatalysis.
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Affiliation(s)
- Risa Fukuzumi
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Marius Buerkle
- CD-FMat, National Institute of Advanced Industrial Science and Technology (AIST), Central 2, Umezono 1-1-1, Tsukuba, Ibaraki, 305-8568, Japan
| | - Yu Li
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Satoshi Kaneko
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Peihui Li
- Institute of Modern Optics, Nankai University, 94 Weijin Road, Tianjin, 300350, P. R. China
| | - Shuji Kobayashi
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Shintaro Fujii
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Manabu Kiguchi
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Hisao Nakamura
- CD-FMat, National Institute of Advanced Industrial Science and Technology (AIST), Central 2, Umezono 1-1-1, Tsukuba, Ibaraki, 305-8568, Japan
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki, 305-0044, Japan
| | - Tomoaki Nishino
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
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Zhao Z, Guo C, Ni L, Zhao X, Zhang S, Xiang D. In situ photoconductivity measurements of imidazole in optical fiber break-junctions. NANOSCALE HORIZONS 2021; 6:386-392. [PMID: 33949578 DOI: 10.1039/d1nh00031d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We developed a method based on the mechanically controllable break junction technique to investigate the electron transport properties of single molecular junctions upon fiber waveguided light. In our strategy, a metal-coated tapered optical fiber is fixed on a flexible substrate, and this tapered fiber serves as both the optical waveguide and metal electrodes after it breaks. For an imidazole bridged single-molecule junction, two probable conductance values below 1G0 are observed. The higher value shows an approximately 40% enhancement under illumination, while the lower one does not show distinguishable difference under illumination. Theoretical calculations reveal these two conductance values resulting from the imidazole monomer junction and the imidazole dimer junction linked via a hydrogen bond, respectively. In imidazole monomer junctions, the absorption of a single photon strongly shifts the transmission function resulting in optical-induced conductance enhancement. In contrast, the transmission function of imidazole dimer junctions remains at the same level in the bias window despite the light illumination. This work provides a robust experimental framework for studying the underlying mechanisms of photoconductivity in single-molecule junctions and offers tools for tuning the optoelectronic performance of single-molecule devices in situ.
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Affiliation(s)
- Zhikai Zhao
- Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology Institute of Modern Optics, Nankai University, Tianjin 300350, China.
| | - Chenyang Guo
- Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology Institute of Modern Optics, Nankai University, Tianjin 300350, China.
| | - Lifa Ni
- Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology Institute of Modern Optics, Nankai University, Tianjin 300350, China.
| | - Xueyan Zhao
- Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology Institute of Modern Optics, Nankai University, Tianjin 300350, China.
| | - Surong Zhang
- Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology Institute of Modern Optics, Nankai University, Tianjin 300350, China.
| | - Dong Xiang
- Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology Institute of Modern Optics, Nankai University, Tianjin 300350, China.
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10
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Zhou P, Zheng J, Han T, Chen L, Cao W, Zhu Y, Zhou D, Li R, Tian Y, Liu Z, Liu J, Hong W. Electrostatic gating of single-molecule junctions based on the STM-BJ technique. NANOSCALE 2021; 13:7600-7605. [PMID: 33928979 DOI: 10.1039/d1nr00157d] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The gating of charge transport through single-molecule junctions is considered a critical step towards molecular circuits but remains challenging. In this work, we report an electrostatic gating method to tune the conductance of single-molecule junctions using the scanning tunneling microscope break junction (STM-BJ) technique incorporated with a back-gated chip as a substrate. We demonstrated that the conductance varied at different applied gating voltages (Vgs). The HOMO-dominated molecules show a decrease in conductance with an increase in Vg, and the LUMO-dominated molecules show the opposite trend. The measured conductance trends with Vg are consistent with the transition voltage spectroscopy measurements. Moreover, the transmission functions simulated from density functional theory (DFT) calculations and the finite element analysis all suggest that Vg changed the energy alignment of the molecular junction. This work provides a simple method for modulating the molecular orbitals' alignment relative to the Fermi energy (Ef) of metal electrodes to explore the charge transport properties at the single-molecule scale.
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Affiliation(s)
- Ping Zhou
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University, 361005, Xiamen, China.
| | - Jueting Zheng
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University, 361005, Xiamen, China.
| | - Tianyang Han
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University, 361005, Xiamen, China.
| | - Lijue Chen
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University, 361005, Xiamen, China.
| | - Wenqiang Cao
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University, 361005, Xiamen, China.
| | - Yixuan Zhu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University, 361005, Xiamen, China.
| | - Dahai Zhou
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University, 361005, Xiamen, China.
| | - Ruihao Li
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University, 361005, Xiamen, China.
| | - Yingyu Tian
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University, 361005, Xiamen, China.
| | - Zitong Liu
- State Key Laboratory of Applied Organic Chemistry (SKLAOC), College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P. R. China
| | - Junyang Liu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University, 361005, Xiamen, China.
| | - Wenjing Hong
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University, 361005, Xiamen, China.
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Lee HJ, Cho SJ, Kang H, He X, Yoon HJ. Achieving Ultralow, Zero, and Inverted Tunneling Attenuation Coefficients in Molecular Wires with Extended Conjugation. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2005711. [PMID: 33543557 DOI: 10.1002/smll.202005711] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/22/2020] [Indexed: 06/12/2023]
Abstract
Molecular tunnel junctions are organic devices miniaturized to the molecular scale. They serve as a versatile toolbox that can systematically examine charge transport behaviors at the atomic level. The electrical conductance of the molecular wire that bridges the two electrodes in a junction is significantly influenced by its chemical structure, and an intrinsically poor conductance is a major barrier for practical applications toward integrating individual molecules into electronic circuitry. Therefore, highly conjugated molecular wires are attractive as active components for the next-generation electronic devices, owing to the narrow highest occupied molecular orbital-lowest occupied molecular orbital gaps provided by their extended π-building blocks. This article aims to highlight the significance of highly conductive molecular wires in molecular electronics, the structures of which are inspired from conductive organic polymers, and presents a body of discussion on molecular wires exhibiting ultralow, zero, or inverted attenuation of tunneling probability at different lengths, along with future directions.
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Affiliation(s)
- Hyun Ju Lee
- Department of Chemistry, Korea University, Seoul, 02841, South Korea
| | - Soo Jin Cho
- Department of Chemistry, Korea University, Seoul, 02841, South Korea
| | - Hungu Kang
- Department of Chemistry, Korea University, Seoul, 02841, South Korea
| | - Xin He
- Department of Chemistry, Korea University, Seoul, 02841, South Korea
| | - Hyo Jae Yoon
- Department of Chemistry, Korea University, Seoul, 02841, South Korea
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12
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Souto DE, Volpe J, Gonçalves CDC, Ramos CH, Kubota LT. A brief review on the strategy of developing SPR-based biosensors for application to the diagnosis of neglected tropical diseases. Talanta 2019; 205:120122. [DOI: 10.1016/j.talanta.2019.120122] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/03/2019] [Accepted: 07/05/2019] [Indexed: 12/22/2022]
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