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Xu X, Gao C, Emusani R, Jia C, Xiang D. Toward Practical Single-Molecule/Atom Switches. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2400877. [PMID: 38810145 PMCID: PMC11304318 DOI: 10.1002/advs.202400877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 04/29/2024] [Indexed: 05/31/2024]
Abstract
Electronic switches have been considered to be one of the most important components of contemporary electronic circuits for processing and storing digital information. Fabricating functional devices with building blocks of atomic/molecular switches can greatly promote the minimization of the devices and meet the requirement of high integration. This review highlights key developments in the fabrication and application of molecular switching devices. This overview offers valuable insights into the switching mechanisms under various stimuli, emphasizing structural and energy state changes in the core molecules. Beyond the molecular switches, typical individual metal atomic switches are further introduced. A critical discussion of the main challenges for realizing and developing practical molecular/atomic switches is provided. These analyses and summaries will contribute to a comprehensive understanding of the switch mechanisms, providing guidance for the rational design of functional nanoswitch devices toward practical applications.
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Affiliation(s)
- Xiaona Xu
- Institute of Modern Optics and Center of Single Molecule SciencesNankai UniversityTianjin Key Laboratory of Micro‐scale Optical Information Science and TechnologyTianjin300350China
| | - Chunyan Gao
- Institute of Modern Optics and Center of Single Molecule SciencesNankai UniversityTianjin Key Laboratory of Micro‐scale Optical Information Science and TechnologyTianjin300350China
| | - Ramya Emusani
- Institute of Modern Optics and Center of Single Molecule SciencesNankai UniversityTianjin Key Laboratory of Micro‐scale Optical Information Science and TechnologyTianjin300350China
| | - Chuancheng Jia
- Institute of Modern Optics and Center of Single Molecule SciencesNankai UniversityTianjin Key Laboratory of Micro‐scale Optical Information Science and TechnologyTianjin300350China
| | - Dong Xiang
- Institute of Modern Optics and Center of Single Molecule SciencesNankai UniversityTianjin Key Laboratory of Micro‐scale Optical Information Science and TechnologyTianjin300350China
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2
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Li Y, Xie J, Sun L, Zeng J, Zhou L, Hao Z, Pan L, Ye J, Wang P, Li Y, Xu J, Shi Y, Wang X, He D. Monolayer Organic Crystals for Ultrahigh Performance Molecular Diodes. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2305100. [PMID: 38145961 PMCID: PMC10933607 DOI: 10.1002/advs.202305100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 12/07/2023] [Indexed: 12/27/2023]
Abstract
Molecular diodes are of considerable interest for the increasing technical demands of device miniaturization. However, the molecular diode performance remains contact-limited, which represents a major challenge for the advancement of rectification ratio and conductance. Here, it is demonstrated that high-quality ultrathin organic semiconductors can be grown on several classes of metal substrates via solution-shearing epitaxy, with a well-controlled number of layers and monolayer single crystal over 1 mm. The crystals are atomically smooth and pinhole-free, providing a native interface for high-performance monolayer molecular diodes. As a result, the monolayer molecular diodes show record-high rectification ratio up to 5 × 108 , ideality factor close to unity, aggressive unit conductance over 103 S cm-2 , ultrahigh breakdown electric field, excellent electrical stability, and well-defined contact interface. Large-area monolayer molecular diode arrays with 100% yield and excellent uniformity in the diode metrics are further fabricated. These results suggest that monolayer molecular crystals have great potential to build reliable, high-performance molecular diodes and deeply understand their intrinsic electronic behavior.
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Affiliation(s)
- Yating Li
- National Laboratory of Solid‐State MicrostructuresSchool of Electronic Science and EngineeringKey Lab of Optoelectronic Devices and Systems with Extreme Performances and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China
| | - Jiacheng Xie
- National Laboratory of Solid‐State MicrostructuresSchool of Electronic Science and EngineeringKey Lab of Optoelectronic Devices and Systems with Extreme Performances and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China
| | - Li Sun
- National Laboratory of Solid‐State MicrostructuresSchool of Electronic Science and EngineeringKey Lab of Optoelectronic Devices and Systems with Extreme Performances and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China
| | - Junpeng Zeng
- National Laboratory of Solid‐State MicrostructuresSchool of Electronic Science and EngineeringKey Lab of Optoelectronic Devices and Systems with Extreme Performances and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China
| | - Liqi Zhou
- National Laboratory of Solid‐State MicrostructuresJiangsu Key Laboratory of Artificial Functional MaterialsCollege of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210023China
| | - Ziqian Hao
- National Laboratory of Solid‐State MicrostructuresSchool of Electronic Science and EngineeringKey Lab of Optoelectronic Devices and Systems with Extreme Performances and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China
| | - Lijia Pan
- National Laboratory of Solid‐State MicrostructuresSchool of Electronic Science and EngineeringKey Lab of Optoelectronic Devices and Systems with Extreme Performances and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China
| | - Jiandong Ye
- National Laboratory of Solid‐State MicrostructuresSchool of Electronic Science and EngineeringKey Lab of Optoelectronic Devices and Systems with Extreme Performances and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China
| | - Peng Wang
- Department of PhysicsUniversity of WarwickCoventryCV4 7ALUnited Kingdom
| | - Yun Li
- National Laboratory of Solid‐State MicrostructuresSchool of Electronic Science and EngineeringKey Lab of Optoelectronic Devices and Systems with Extreme Performances and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China
| | - Jian‐Bin Xu
- Department of Electronic Engineering and Materials Science and Technology Research CenterThe Chinese University of Hong KongHong Kong999077China
| | - Yi Shi
- National Laboratory of Solid‐State MicrostructuresSchool of Electronic Science and EngineeringKey Lab of Optoelectronic Devices and Systems with Extreme Performances and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China
| | - Xinran Wang
- National Laboratory of Solid‐State MicrostructuresSchool of Electronic Science and EngineeringKey Lab of Optoelectronic Devices and Systems with Extreme Performances and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China
- School of Integrated CircuitsNanjing UniversitySuzhou215163China
| | - Daowei He
- National Laboratory of Solid‐State MicrostructuresSchool of Electronic Science and EngineeringKey Lab of Optoelectronic Devices and Systems with Extreme Performances and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China
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3
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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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Li T, Hantusch M, Qu J, Bandari VK, Knupfer M, Zhu F, Schmidt OG. On-chip integrated process-programmable sub-10 nm thick molecular devices switching between photomultiplication and memristive behaviour. Nat Commun 2022; 13:2875. [PMID: 35610214 PMCID: PMC9130281 DOI: 10.1038/s41467-022-30498-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 05/05/2022] [Indexed: 11/24/2022] Open
Abstract
Molecular devices constructed by sub-10 nm thick molecular layers are promising candidates for a new generation of integratable nanoelectronic applications. Here, we report integrated molecular devices based on ultrathin copper phthalocyanine/fullerene hybrid layers with microtubular soft-contacts, which exhibit process-programmable functionality switching between photomultiplication and memristive behaviour. The local electric field at the interface between the polymer bottom electrode and the enclosed molecular channels modulates the ionic-electronic charge interaction and hence determines the transition of the device function. When ions are not driven into the molecular channels at a low interface electric field, photogenerated holes are trapped as electronic space charges, resulting in photomultiplication with a high external quantum efficiency. Once mobile ions are polarized and accumulated as ionic space charges in the molecular channels at a high interface electric field, the molecular devices show ferroelectric-like memristive switching with remarkable resistive ON/OFF and rectification ratios.
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Affiliation(s)
- Tianming Li
- Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany
- Institute for Integrative Nanosciences, Leibniz IFW Dresden, 01069, Dresden, Germany
| | - Martin Hantusch
- Institute for Solid State Research, Leibniz IFW Dresden, 01069, Dresden, Germany
| | - Jiang Qu
- Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany
- Institute for Integrative Nanosciences, Leibniz IFW Dresden, 01069, Dresden, Germany
| | - Vineeth Kumar Bandari
- Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany
- Institute for Integrative Nanosciences, Leibniz IFW Dresden, 01069, Dresden, Germany
| | - Martin Knupfer
- Institute for Solid State Research, Leibniz IFW Dresden, 01069, Dresden, Germany
| | - Feng Zhu
- Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany.
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany.
- Institute for Integrative Nanosciences, Leibniz IFW Dresden, 01069, Dresden, Germany.
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, China.
| | - Oliver G Schmidt
- Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany.
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany.
- Institute for Integrative Nanosciences, Leibniz IFW Dresden, 01069, Dresden, Germany.
- School of Science, Dresden University of Technology, 01069, Dresden, Germany.
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Xie Z, Diez Cabanes V, Van Nguyen Q, Rodriguez-Gonzalez S, Norel L, Galangau O, Rigaut S, Cornil J, Frisbie CD. Quantifying Image Charge Effects in Molecular Tunnel Junctions Based on Self-Assembled Monolayers of Substituted Oligophenylene Ethynylene Dithiols. ACS APPLIED MATERIALS & INTERFACES 2021; 13:56404-56412. [PMID: 34783518 DOI: 10.1021/acsami.1c16398] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A number of factors contribute to orbital energy alignment with respect to the Fermi level in molecular tunnel junctions. Here, we report a combined experimental and theoretical effort to quantify the effect of metal image potentials on the highest occupied molecular orbital to Fermi level offset, εh, for molecular junctions based on self-assembled monolayers (SAMs) of oligophenylene ethynylene dithiols (OPX) on Au. Our experimental approach involves the use of both transport and photoelectron spectroscopy to extract the offsets, εhtrans and εhUPS, respectively. We take the difference in these quantities to be the image potential energy eVimage. In the theoretical approach, we use density functional theory (DFT) to calculate directly eVimage between positive charge on an OPX molecule and the negative image charge in the Au. Both approaches yield eVimage ∼ -0.1 eV per metal contact, meaning that the total image potential energy is ∼-0.2 eV for an assembled junction with two Au contacts. Thus, we find that the total image potential energy is 25-30% of the total offset εh, which means that image charge effects are significant in OPX junctions. Our methods should be generally applicable to understanding image charge effects as a function of molecular size, for example, in a variety of SAM-based junctions.
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Affiliation(s)
- Zuoti Xie
- Department of Materials Science and Engineering, Guangdong Technion-Israel Institute of Technology, Shantou, Guangdong 515063, China
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Valentin Diez Cabanes
- Laboratory for Chemistry of Novel Materials, University of Mons, Mons B-7000, Belgium
| | - Quyen Van Nguyen
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Sandra Rodriguez-Gonzalez
- Laboratory for Chemistry of Novel Materials, University of Mons, Mons B-7000, Belgium
- Department of Physical Chemistry, University of Malaga, Campus de Teatinos s/n, Malaga 29071, Spain
| | - Lucie Norel
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, Rennes F-3500, France
| | - Olivier Galangau
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, Rennes F-3500, France
| | - Stéphane Rigaut
- Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)-UMR 6226, Rennes F-3500, France
| | - Jérôme Cornil
- Laboratory for Chemistry of Novel Materials, University of Mons, Mons B-7000, Belgium
| | - C Daniel Frisbie
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
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6
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Kargeti A, Rasheed T, Ahmad Siddiqui S. Utilization of asymmetrical electron transport as strategy for modelling and design of efficient single molecule diodes: A DFT investigation. COMPUT THEOR CHEM 2021. [DOI: 10.1016/j.comptc.2021.113441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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7
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Cai K, Zhang L, Astumian RD, Stoddart JF. Radical-pairing-induced molecular assembly and motion. Nat Rev Chem 2021; 5:447-465. [PMID: 37118435 DOI: 10.1038/s41570-021-00283-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/16/2021] [Indexed: 12/25/2022]
Abstract
Radical-pairing interactions between conjugated organic π-radicals are relative newcomers to the inventory of molecular recognition motifs explored in supramolecular chemistry. The unique electronic, magnetic, optical and redox-responsive properties of the conjugated π-radicals render molecules designed with radical-pairing interactions useful for applications in various areas of chemistry and materials science. In particular, the ability to control formation of radical cationic or anionic species, by redox stimulation, provides a flexible trigger for directed assembly and controlled molecular motions, as well as a convenient means of inputting energy to fuel non-equilibrium processes. In this Review, we provide an overview of different examples of radical-pairing-based recognition processes and of their emerging use in (1) supramolecular assembly, (2) templation of mechanically interlocked molecules, (3) stimuli-controlled molecular switches and, by incorporation of kinetic asymmetry in the design, (4) the creation of unidirectional molecular transporters based on pumping cassettes powered by fuelled switching of radical-pairing interactions. We conclude the discussion with an outlook on future directions for the field.
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8
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Gupta NK, Schultz T, Karuppannan SK, Vilan A, Koch N, Nijhuis CA. The energy level alignment of the ferrocene-EGaIn interface studied with photoelectron spectroscopy. Phys Chem Chem Phys 2021; 23:13458-13467. [PMID: 34095913 DOI: 10.1039/d1cp01690c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The energy level alignment after the formation of a molecular tunnel junction is often poorly understood because spectroscopy inside junctions is not possible, which hampers the rational design of functional molecular junctions and complicates the interpretation of the data generated by molecular junctions. In molecular junction platforms where the top electrode-molecule interaction is weak; one may argue that the energy level alignment can be deduced from measurements with the molecules supported by the bottom electrode (sometimes referred to as "half junctions"). This approach, however, still relies on a series of assumptions, which are challenging to address experimentally due to difficulties in studying the molecule-top electrode interaction. Herein, we describe top electrode-molecule junctions with a liquid metal alloy top electrode of EGaIn (which stands for eutectic alloy of Ga and In) interacting with well-characterised ferrocene (Fc) moieties. We deposited a ferrocene derivative on films of EGaIn, coated with its native GaOx layer, and studied the energy level alignment with photoelectron spectroscopy. Our results reveal that the electronic interaction between the Fc and GaOx/EGaIn is very weak, resembling physisorption. Therefore, investigations of "half junctions" for this system can provide valuable information regarding the energy level alignment of complete EGaIn junctions. Our results help to improve our understanding of the energy landscape in weakly coupled molecular junctions and aid to the rational design of molecular electronic devices.
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Affiliation(s)
- Nipun Kumar Gupta
- Departement of Chemistry, Faculty of Science, National University of Singapore, Singapore, Singapore and Centre for Advanced 2D Materials, National University of Singapore, 6 Science Drive 2, Singapore 117546, Singapore
| | - Thorsten Schultz
- Institut für Physik, Humboldt-Universität zu Berlin, Newtonstraße 15, 12489 Berlin, Germany. and Helmholtz Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein Straße 15, 12489 Berlin, Germany
| | - Senthil Kumar Karuppannan
- Departement of Chemistry, Faculty of Science, National University of Singapore, Singapore, Singapore
| | - Ayelet Vilan
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Norbert Koch
- Institut für Physik, Humboldt-Universität zu Berlin, Newtonstraße 15, 12489 Berlin, Germany. and Helmholtz Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein Straße 15, 12489 Berlin, Germany
| | - Christian A Nijhuis
- Departement of Chemistry, Faculty of Science, National University of Singapore, Singapore, Singapore and Centre for Advanced 2D Materials, National University of Singapore, 6 Science Drive 2, Singapore 117546, Singapore and Department of Molecules and Materials, MESA+ Institute for Nanotechnology and Center for Brain-Inspired Nano Systems, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
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9
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Oberoi D, Dagar P, Shankar U, Sahu S, Bandyopadhyay A. Stabilization of Pristine Low Resistive State in a Ruthenium(II)‐Polymer of a Hexadentate Schiff Base Ligand: Synthesis, Characterization, and Application as Non‐Volatile Memory Device. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000303] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Deepa Oberoi
- Department of Chemistry NIT Tiruchirappalli 620015 Tiruchirappalli Tamil Nadu India
- Department of Polymer & Process Engineering IIT Roorkee, IIT Roorkee Saharanpur Campus 247001 Saharanpur India
| | - Parveen Dagar
- Department of Physics IIT Jodhpur 342011 Jodhpur India
| | - Uday Shankar
- Department of Polymer & Process Engineering IIT Roorkee, IIT Roorkee Saharanpur Campus 247001 Saharanpur India
| | - Satyajit Sahu
- Department of Physics IIT Jodhpur 342011 Jodhpur India
| | - Anasuya Bandyopadhyay
- Department of Polymer & Process Engineering IIT Roorkee, IIT Roorkee Saharanpur Campus 247001 Saharanpur India
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Han Y, Nickle C, Zhang Z, Astier HPAG, Duffin TJ, Qi D, Wang Z, Del Barco E, Thompson D, Nijhuis CA. Electric-field-driven dual-functional molecular switches in tunnel junctions. NATURE MATERIALS 2020; 19:843-848. [PMID: 32483243 DOI: 10.1038/s41563-020-0697-5] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 04/28/2020] [Indexed: 05/24/2023]
Abstract
To avoid crosstalk and suppress leakage currents in resistive random access memories (RRAMs), a resistive switch and a current rectifier (diode) are usually combined in series in a one diode-one resistor (1D-1R) RRAM. However, this complicates the design of next-generation RRAM, increases the footprint of devices and increases the operating voltage as the potential drops over two consecutive junctions1. Here, we report a molecular tunnel junction based on molecules that provide an unprecedented dual functionality of diode and variable resistor, resulting in a molecular-scale 1D-1R RRAM with a current rectification ratio of 2.5 × 104 and resistive on/off ratio of 6.7 × 103, and a low drive voltage of 0.89 V. The switching relies on dimerization of redox units, resulting in hybridization of molecular orbitals accompanied by directional ion migration. This electric-field-driven molecular switch operating in the tunnelling regime enables a class of molecular devices where multiple electronic functions are preprogrammed inside a single molecular layer with a thickness of only 2 nm.
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Affiliation(s)
- Yingmei Han
- Department of Chemistry, National University of Singapore, Singapore, Singapore
| | - Cameron Nickle
- Department of Physics, University of Central Florida, Orlando, FL, USA
| | - Ziyu Zhang
- Department of Chemistry, National University of Singapore, Singapore, Singapore
| | | | - Thorin J Duffin
- Department of Chemistry, National University of Singapore, Singapore, Singapore
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, Singapore
| | - Dongchen Qi
- Centre for Materials Science, School of Chemistry and Physics, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Zhe Wang
- Department of Chemistry, National University of Singapore, Singapore, Singapore
| | - Enrique Del Barco
- Department of Physics, University of Central Florida, Orlando, FL, USA.
| | - Damien Thompson
- Department of Physics, Bernal Institute, University of Limerick, Limerick, Ireland.
| | - Christian A Nijhuis
- Department of Chemistry, National University of Singapore, Singapore, Singapore.
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, Singapore.
- Centre for Advanced 2D Materials and Graphene Research Center, National University of Singapore, Singapore, Singapore.
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11
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Chiang TM, Hsu LY. Quantum transport with electronic relaxation in electrodes: Landauer-type formulas derived from the driven Liouville-von Neumann approach. J Chem Phys 2020; 153:044103. [PMID: 32752664 DOI: 10.1063/5.0007750] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We derive the exact steady-state solutions for the simplest model systems of resonant tunneling and tunneling with destructive quantum interference from the driven Liouville-von Neumann (DLvN) approach. Under the finite-state lead condition (the two electrodes have finite states), we analyze the asymptotic behavior of the steady-state current in the two limits of electronic relaxation. Under the infinite-state lead condition, the steady-state solutions of the two model systems can be cast as Landauer-type current formulas. According to the formulas, we show that the transmission functions near the resonant peak and the antiresonant dip can be significantly influenced by electronic relaxation in the electrodes. Moreover, under intermediate and strong electronic relaxation conditions, we analytically show that the steady-state current of the DLvN approach dramatically deviates from the Landauer current when destructive quantum interference occurs. In the regime of zero electronic relaxation, our results are reduced to the Landauer formula, indicating that the DLvN approach is equivalent to the Landauer approach when the leads have infinite states without any electronic relaxation.
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Affiliation(s)
- Tse-Min Chiang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Liang-Yan Hsu
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
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12
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Li T, Bandari VK, Hantusch M, Xin J, Kuhrt R, Ravishankar R, Xu L, Zhang J, Knupfer M, Zhu F, Yan D, Schmidt OG. Integrated molecular diode as 10 MHz half-wave rectifier based on an organic nanostructure heterojunction. Nat Commun 2020; 11:3592. [PMID: 32680989 PMCID: PMC7368027 DOI: 10.1038/s41467-020-17352-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 06/23/2020] [Indexed: 11/23/2022] Open
Abstract
Considerable efforts have been made to realize nanoscale diodes based on single molecules or molecular ensembles for implementing the concept of molecular electronics. However, so far, functional molecular diodes have only been demonstrated in the very low alternating current frequency regime, which is partially due to their extremely low conductance and the poor degree of device integration. Here, we report about fully integrated rectifiers with microtubular soft-contacts, which are based on a molecularly thin organic heterojunction and are able to convert alternating current with a frequency of up to 10 MHz. The unidirectional current behavior of our devices originates mainly from the intrinsically different surfaces of the bottom planar and top microtubular Au electrodes while the excellent high frequency response benefits from the charge accumulation in the phthalocyanine molecular heterojunction, which not only improves the charge injection but also increases the carrier density. The demand for miniaturization of electronics has been motivating a growing interest in high-performance molecular electronics. Li, Bandari et al. report a fully integrated molecular rectifier based on a molecular heterojunction and microtubular electrode enabling high frequency operation at more than 10 MHz.
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Affiliation(s)
- Tianming Li
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany.,Institute for Integrative Nanosciences, Leibniz IFW Dresden, 01069, Dresden, Germany.,Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany
| | - Vineeth Kumar Bandari
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany.,Institute for Integrative Nanosciences, Leibniz IFW Dresden, 01069, Dresden, Germany.,Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany
| | - Martin Hantusch
- Institute for Solid State Research, Leibniz IFW Dresden, 01069, Dresden, Germany
| | - Jianhui Xin
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
| | - Robert Kuhrt
- Institute for Solid State Research, Leibniz IFW Dresden, 01069, Dresden, Germany
| | - Rachappa Ravishankar
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany.,Institute for Integrative Nanosciences, Leibniz IFW Dresden, 01069, Dresden, Germany
| | - Longqian Xu
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany.,Institute for Integrative Nanosciences, Leibniz IFW Dresden, 01069, Dresden, Germany
| | - Jidong Zhang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
| | - Martin Knupfer
- Institute for Solid State Research, Leibniz IFW Dresden, 01069, Dresden, Germany
| | - Feng Zhu
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany. .,Institute for Integrative Nanosciences, Leibniz IFW Dresden, 01069, Dresden, Germany. .,Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany. .,State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China.
| | - Donghang Yan
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
| | - Oliver G Schmidt
- Material Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany.,Institute for Integrative Nanosciences, Leibniz IFW Dresden, 01069, Dresden, Germany.,Center for Materials, Architectures and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09126, Chemnitz, Germany
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13
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Vuillaume D. Molecular Electronics: From Single‐Molecule to Large‐Area Devices. Chempluschem 2019; 84:1215-1221. [DOI: 10.1002/cplu.201900171] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/08/2019] [Indexed: 11/09/2022]
Affiliation(s)
- Dominique Vuillaume
- Institute for Electronics Microelectronics and Nanotechnology CNRSUniversité de Lille Avenue Poincaré CS60069, 59652 cedex Villeneuve d'Ascq France
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14
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Cao L, Yuan L, Yang M, Nerngchamnong N, Thompson D, Yu X, Qi DC, Nijhuis CA. The supramolecular structure and van der Waals interactions affect the electronic structure of ferrocenyl-alkanethiolate SAMs on gold and silver electrodes. NANOSCALE ADVANCES 2019; 1:1991-2002. [PMID: 36134247 PMCID: PMC9417838 DOI: 10.1039/c9na00107g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 03/20/2019] [Indexed: 06/12/2023]
Abstract
Understanding the influence of structural properties on the electronic structure will pave the way for optimization of charge transport properties of SAM devices. In this study, we systematically investigate the supramolecular and electronic structures of ferrocene (Fc) terminated alkanethiolate (SC n Fc) SAMs on both Au and Ag substrates with n = 1-15 by using a combination of synchrotron based near edge X-ray absorption spectroscopy (NEXAFS), photoemission spectroscopy (PES), and density functional theory (DFT) calculations. Odd-even effects in the supramolecular structure persist over the entire range of n = 1-15, which, in turn, explain the odd-even effects in the onset energy of the highest occupied molecular (HOMO) orbital. The orientation of the Fc moieties and the strength of Fc-substrate coupling, which both depend on n, affects the work function (WF). The variation of WF shows an odd-even effect in the weak electrode-Fc coupling regime for n ≥ 8, whereas the odd-even effect diminishes for n < 8 due to hybridization between Fc and the electrode (n < 3) or van der Waals (vdW) interactions between Fc and the electrode (n = 3-7). These results confirm that subtle changes in the supramolecular structure of the SAMs cause significant electronic changes that have a large influence on device properties.
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Affiliation(s)
- Liang Cao
- Department of Chemistry, National University of Singapore 3 Science Drive 3 Singapore 117543 Singapore
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences 350 Shushanhu Road Hefei 230031 China
- Department of Physics, National University of Singapore 2 Science Drive 3 Singapore 117542 Singapore
| | - Li Yuan
- Department of Chemistry, National University of Singapore 3 Science Drive 3 Singapore 117543 Singapore
| | - Ming Yang
- Institute of Materials Research and Engineering (IMRE), Innovis 2 Fusionopolis Way Singapore 138634 Singapore
| | - Nisachol Nerngchamnong
- Department of Chemistry, National University of Singapore 3 Science Drive 3 Singapore 117543 Singapore
| | - Damien Thompson
- Department of Physics, Bernal Institute, University of Limerick V94 T9PX Ireland
| | - Xiaojiang Yu
- Singapore Synchrotron Light Source, National University of Singapore 5 Research Link Singapore 117603 Singapore
| | - Dong-Chen Qi
- School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology Brisbane Queensland 4001 Australia
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University Melbourne Victoria 3086 Australia
| | - Christian A Nijhuis
- Department of Chemistry, National University of Singapore 3 Science Drive 3 Singapore 117543 Singapore
- Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore 6 Science Drive 2 Singapore 117546 Singapore
- NUSNNI-Nanocore, National University of Singapore Singapore 117411 Singapore
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15
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Keeler AJ, Russell AE. Potential dependent orientation of sulfanylbenzonitrile monolayers monitored by SERS. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2019.03.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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16
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Kawauchi T, Kojima T, Sakaguchi H, Iyoda T. Electrostatic Repulsion-Induced Desorption of Dendritic Viologen-Arranged Molecules Anchored on a Gold Surface through a Gold-Thiolate Bond Leading to a Tunable Molecular Template. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:6420-6427. [PMID: 29733659 DOI: 10.1021/acs.langmuir.8b00858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We investigated the adsorption and desorption behavior of self-assembled monolayers (SAMs) on gold derived from dendritic viologen-arranged molecules with an ω-mercaptodecyl group (A n, n (dendritic generation) = 0-3) at the apex of the dendritic structure in polar solvents. The adsorption of the dendritic molecules occurred quickly and saturated within a few minutes in an acetonitrile/ethanol (1/1, v/v) mixture at a concentration of 2 mM. Atomic force microscopy images of the SAMs showed flat surfaces regardless of the dendritic generation because the peripheral viologen units were closely packed at the surface of the molecular layer. Individual A3 molecules immobilized on the substrate were observed by scanning tunneling microscopy measurements of a mixed SAM with decanethiol. The desorption behaviors of dendritic molecules from the A n-SAMs in several solvents such as water were also investigated. The spontaneous desorption of the A n-SAM occurred more rapidly than that of a conventional n-alkanethiol SAM. However, the desorption was inhibited by adding electrolytes such as NaNO3 due to the shielding effect on the electrostatic repulsion between the dendritic molecules. These results indicate that the surface density of the dendritic molecules can be controlled through the desorption.
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Affiliation(s)
- Takehiro Kawauchi
- Department of Materials Chemistry, Faculty of Science and Technology , Ryukoku University , 1-5 Yokotani , Oe-cho, Seta, Otsu , Shiga 520-2194 , Japan
| | - Takahiro Kojima
- Institute of Advanced Energy , Kyoto University , Gokasyo, Uji , Kyoto 611-0011 , Japan
| | - Hiroshi Sakaguchi
- Institute of Advanced Energy , Kyoto University , Gokasyo, Uji , Kyoto 611-0011 , Japan
| | - Tomokazu Iyoda
- Harris Science Research Institute , Doshisha University , 1-3 Tatara Miyakodani , Kyotanabe , Kyoto 610-0394 , Japan
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17
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Jiang Y. Quantum interference in multi-branched molecules: The exact transfer matrix solutions. J Chem Phys 2017; 147:214115. [PMID: 29221391 DOI: 10.1063/1.4989872] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
We present a transfer matrix formalism for studying quantum interference in a single molecule electronic system with internal branched structures. Based on the Schrödinger equation with the Bethe ansatz and employing Kirchhoff's rule for quantum wires, we derive a general closed-form expression for the transmission and reflection amplitudes of a two-port quantum network. We show that the transport through a molecule with complex internal structures can be reduced to that of a single two-port scattering unit, which contains all the information of the original composite molecule. Our method allows for the calculation of the transmission coefficient for various types of individual molecular modules giving rise to different resonant transport behaviors such as the Breit-Wigner, Fano, and Mach-Zehnder resonances. As an illustration, we first re-derive the transmittance of the Aharonov-Bohm ring, and then we apply our formulation to N identical parity-time (PT)-symmetric potentials, connected in series as well as in parallel. It is shown that the spectral singularities and PT-symmetric transitions of single scattering cells may be observed in coupled systems. Such transitions may occur at the same or distinct values of the critical parameters, depending on the connection modes under which the scattering objects are coupled.
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Affiliation(s)
- Yu Jiang
- Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, A. P. 55-534, 09340 México D.F., Mexico
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18
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Towards Rectifying Performance at the Molecular Scale. Top Curr Chem (Cham) 2017; 375:85. [DOI: 10.1007/s41061-017-0170-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 09/22/2017] [Indexed: 01/09/2023]
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19
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Nguyen QV, Martin P, Frath D, Della Rocca ML, Lafolet F, Barraud C, Lafarge P, Mukundan V, James D, McCreery RL, Lacroix JC. Control of Rectification in Molecular Junctions: Contact Effects and Molecular Signature. J Am Chem Soc 2017; 139:11913-11922. [DOI: 10.1021/jacs.7b05732] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Quyen van Nguyen
- Université Paris Diderot, Sorbonne Paris
Cité, ITODYS, UMR 7086 CNRS, 15 rue Jean-Antoine de Baïf, 75205 Paris Cedex 13, France
- Department
of Advanced Materials Science and Nanotechnology, University of Science and Technology of Hanoi (USTH), Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam
| | - Pascal Martin
- Université Paris Diderot, Sorbonne Paris
Cité, ITODYS, UMR 7086 CNRS, 15 rue Jean-Antoine de Baïf, 75205 Paris Cedex 13, France
| | - Denis Frath
- Université Paris Diderot, Sorbonne Paris
Cité, ITODYS, UMR 7086 CNRS, 15 rue Jean-Antoine de Baïf, 75205 Paris Cedex 13, France
| | - Maria Luisa Della Rocca
- Laboratoire
Matériaux et Phénomènes Quantiques (MPQ), Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris Cedex 13, France
| | - Frederic Lafolet
- Université Paris Diderot, Sorbonne Paris
Cité, ITODYS, UMR 7086 CNRS, 15 rue Jean-Antoine de Baïf, 75205 Paris Cedex 13, France
| | - Clément Barraud
- Laboratoire
Matériaux et Phénomènes Quantiques (MPQ), Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris Cedex 13, France
| | - Philippe Lafarge
- Laboratoire
Matériaux et Phénomènes Quantiques (MPQ), Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris Cedex 13, France
| | - Vineetha Mukundan
- University of Alberta, National Institute
for Nanotechnology, 11421
Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
| | - David James
- University of Alberta, National Institute
for Nanotechnology, 11421
Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
| | - Richard L. McCreery
- University of Alberta, National Institute
for Nanotechnology, 11421
Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
| | - Jean-Christophe Lacroix
- Université Paris Diderot, Sorbonne Paris
Cité, ITODYS, UMR 7086 CNRS, 15 rue Jean-Antoine de Baïf, 75205 Paris Cedex 13, France
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20
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Jeong H, Kim D, Xiang D, Lee T. High-Yield Functional Molecular Electronic Devices. ACS NANO 2017; 11:6511-6548. [PMID: 28578582 DOI: 10.1021/acsnano.7b02967] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
An ultimate goal of molecular electronics, which seeks to incorporate molecular components into electronic circuit units, is to generate functional molecular electronic devices using individual or ensemble molecules to fulfill the increasing technical demands of the miniaturization of traditional silicon-based electronics. This review article presents a summary of recent efforts to pursue this ultimate aim, covering the development of reliable device platforms for high-yield ensemble molecular junctions and their utilization in functional molecular electronic devices, in which distinctive electronic functionalities are observed due to the functional molecules. In addition, other aspects pertaining to the practical application of molecular devices such as manufacturing compatibility with existing complementary metal-oxide-semiconductor technology, their integration, and flexible device applications are also discussed. These advances may contribute to a deeper understanding of charge transport characteristics through functional molecular junctions and provide a desirable roadmap for future practical molecular electronics applications.
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Affiliation(s)
- Hyunhak Jeong
- Department of Physics and Astronomy, and Institute of Applied Physics, Seoul National University , Seoul 08826, Korea
| | - Dongku Kim
- Department of Physics and Astronomy, and Institute of Applied Physics, Seoul National University , Seoul 08826, Korea
| | - Dong Xiang
- Key Laboratory of Optical Information Science and Technology, Institute of Modern Optics, College of Electronic Information and Optical Engineering, Nankai University , Tianjin 300071, China
| | - Takhee Lee
- Department of Physics and Astronomy, and Institute of Applied Physics, Seoul National University , Seoul 08826, Korea
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21
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Zhang Y, Qiu X, Gordiichuk P, Soni S, Krijger TL, Herrmann A, Chiechi RC. Mechanically and Electrically Robust Self-Assembled Monolayers for Large-Area Tunneling Junctions. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2017; 121:14920-14928. [PMID: 28729893 PMCID: PMC5512119 DOI: 10.1021/acs.jpcc.7b03853] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 06/12/2017] [Indexed: 05/28/2023]
Abstract
This paper examines the relationship between mechanical deformation and the electronic properties of self-assembled monolayers (SAMs) of the oligothiophene 4-([2,2':5',2″:5″,2‴-quaterthiophen]-5-yl)butane-1-thiol (T4C4) in tunneling junctions using conductive probe atomic force microscopy (CP-AFM) and eutectic Ga-In (EGaIn). We compared shifts in conductivity, transition voltages of T4C4 with increasing AFM tip loading force to alkanethiolates. While these shifts result from an increasing tilt angle from penetration of the SAM by the AFM tip for the latter, we ascribe them to distortions of the π system present in T4C4, which is more mechanically robust than alkanethiolates of comparable length; SAMs comprising T4C4 shows about five times higher Young's modulus than alkanethiolates. Density functional theory calculations confirm that mechanical deformations shift the barrier height due to changes in the frontier orbitals caused by small rearrangements to the conformation of the quaterthiophene moiety. The mechanical robustness of T4C4 manifests as an increased tolerance to high bias in large-area EGaIn junctions suggesting that electrostatic pressure plays a significant role in the shorting of molecular junctions at high bias.
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Affiliation(s)
- Yanxi Zhang
- Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Xinkai Qiu
- Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Pavlo Gordiichuk
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Saurabh Soni
- Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Theodorus L. Krijger
- Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Andreas Herrmann
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Ryan C. Chiechi
- Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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22
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Park S, Park JH, Hwang S, Kwak J. Programmable Electrochemical Rectifier Based on a Thin-Layer Cell. ACS APPLIED MATERIALS & INTERFACES 2017; 9:20955-20962. [PMID: 28541653 DOI: 10.1021/acsami.7b02215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A programmable electrochemical rectifier based on thin-layer electrochemistry is described here. Both the rectification ratio and the response time of the device are programmable by controlling the gap distance of the thin-layer electrochemical cell, which is easily controlled using commercially available beads. One of the electrodes was modified using a ferrocene-terminated self-assembled monolayer to offer unidirectional charge transfers via soluble redox species. The thin-layer configuration provided enhanced mass transport, which was determined by the gap thickness. The device with the smallest gap thickness (∼4 μm) showed an unprecedented, high rectification ratio (up to 160) with a fast response time in a two-terminal configuration using conventional electronics.
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Affiliation(s)
- Seungjin Park
- Department of Chemistry, Korea Advanced Institute of Science and Technology , Daejeon 34141, Korea
| | - Jun Hui Park
- Department of Chemistry Education and Institute of Fusion Science, Chonbuk National University , Jeonju 54896, Korea
| | - Seongpil Hwang
- Department of Advanced Materials Chemistry, Korea University , Sejong 30019, Korea
| | - Juhyoun Kwak
- Department of Chemistry, Korea Advanced Institute of Science and Technology , Daejeon 34141, Korea
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23
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Vilan A, Aswal D, Cahen D. Large-Area, Ensemble Molecular Electronics: Motivation and Challenges. Chem Rev 2017; 117:4248-4286. [DOI: 10.1021/acs.chemrev.6b00595] [Citation(s) in RCA: 243] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Ayelet Vilan
- Department
of Materials and Interfaces, Weizmann Institute of Science, Rehovot, Israel
| | | | - David Cahen
- Department
of Materials and Interfaces, Weizmann Institute of Science, Rehovot, Israel
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24
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Hsu LY, Rabitz H. Theory of molecular conductance using a modular approach. J Chem Phys 2016; 145:234702. [DOI: 10.1063/1.4972131] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Liang-Yan Hsu
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
| | - Herschel Rabitz
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
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25
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Carlotti M, Kovalchuk A, Wächter T, Qiu X, Zharnikov M, Chiechi RC. Conformation-driven quantum interference effects mediated by through-space conjugation in self-assembled monolayers. Nat Commun 2016; 7:13904. [PMID: 27996036 PMCID: PMC5187444 DOI: 10.1038/ncomms13904] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 11/10/2016] [Indexed: 11/09/2022] Open
Abstract
Tunnelling currents through tunnelling junctions comprising molecules with cross-conjugation are markedly lower than for their linearly conjugated analogues. This effect has been shown experimentally and theoretically to arise from destructive quantum interference, which is understood to be an intrinsic, electronic property of molecules. Here we show experimental evidence of conformation-driven interference effects by examining through-space conjugation in which π-conjugated fragments are arranged face-on or edge-on in sufficiently close proximity to interact through space. Observing these effects in the latter requires trapping molecules in a non-equilibrium conformation closely resembling the X-ray crystal structure, which we accomplish using self-assembled monolayers to construct bottom-up, large-area tunnelling junctions. In contrast, interference effects are completely absent in zero-bias simulations on the equilibrium, gas-phase conformation, establishing through-space conjugation as both of fundamental interest and as a potential tool for tuning tunnelling charge-transport in large-area, solid-state molecular-electronic devices.
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Affiliation(s)
- Marco Carlotti
- Stratingh Institute for Chemistry &Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands
| | - Andrii Kovalchuk
- Stratingh Institute for Chemistry &Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands
| | - Tobias Wächter
- Applied Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 253, Heidelberg 69120, Germany
| | - Xinkai Qiu
- Stratingh Institute for Chemistry &Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands
| | - Michael Zharnikov
- Applied Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 253, Heidelberg 69120, Germany
| | - Ryan C Chiechi
- Stratingh Institute for Chemistry &Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands
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26
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Lamport ZA, Broadnax AD, Harrison D, Barth KJ, Mendenhall L, Hamilton CT, Guthold M, Thonhauser T, Welker ME, Jurchescu OD. Fluorinated benzalkylsilane molecular rectifiers. Sci Rep 2016; 6:38092. [PMID: 27897250 PMCID: PMC5126687 DOI: 10.1038/srep38092] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 11/03/2016] [Indexed: 11/26/2022] Open
Abstract
We report on the synthesis and electrical properties of nine new alkylated silane self-assembled monolayers (SAMs) – (EtO)3Si(CH2)nN = CHPhX where n = 3 or 11 and X = 4-CF3, 3,5-CF3, 3-F-4-CF3, 4-F, or 2,3,4,5,6-F, and explore their rectification behavior in relation to their molecular structure. The electrical properties of the films were examined in a metal/insulator/metal configuration, with a highly-doped silicon bottom contact and a eutectic gallium-indium liquid metal (EGaIn) top contact. The junctions exhibit high yields (>90%), a remarkable resistance to bias stress, and current rectification ratios (R) between 20 and 200 depending on the structure, degree of order, and internal dipole of each molecule. We found that the rectification ratio correlates positively with the strength of the molecular dipole moment and it is reduced with increasing molecular length.
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Affiliation(s)
- Zachary A Lamport
- Department of Physics, Wake Forest University, Winston Salem, NC 27109, USA
| | - Angela D Broadnax
- Department of Chemistry, Wake Forest University, Winston Salem, NC 27109, USA
| | - David Harrison
- Department of Physics, Wake Forest University, Winston Salem, NC 27109, USA
| | - Katrina J Barth
- Department of Physics, Wake Forest University, Winston Salem, NC 27109, USA
| | - Lee Mendenhall
- Department of Chemistry, Wake Forest University, Winston Salem, NC 27109, USA
| | - Clayton T Hamilton
- Department of Chemistry, Wake Forest University, Winston Salem, NC 27109, USA
| | - Martin Guthold
- Department of Physics, Wake Forest University, Winston Salem, NC 27109, USA
| | - Timo Thonhauser
- Department of Physics, Wake Forest University, Winston Salem, NC 27109, USA.,Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Mark E Welker
- Department of Chemistry, Wake Forest University, Winston Salem, NC 27109, USA
| | - Oana D Jurchescu
- Department of Physics, Wake Forest University, Winston Salem, NC 27109, USA
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27
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Wang Z, Chen J, Gathiaka SM, Oyola-Reynoso S, Thuo M. Effect of Substrate Morphology on the Odd-Even Effect in Hydrophobicity of Self-Assembled Monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:10358-10367. [PMID: 27642814 DOI: 10.1021/acs.langmuir.6b01681] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Surface roughness, often captured through root-mean-square roughness (Rrms), has been shown to impact the quality of self-assembled monolayers (SAMs) formed on coinage metals. Understanding the effect of roughness on hydrophobicity of SAMs, however, is complicated by the odd-even effect-a zigzag oscillation in contact angles with changes in molecular length. We recently showed that for surfaces with Rrms > 1 nm, the odd-even effect in hydrophobicity cannot be empirically observed. In this report, we compare wetting properties of SAMs on Ag and Au surfaces of different morphologies across the Rrms ∼ 1 nm limit. We prepared surfaces with comparable properties (grain sizes and Rrms) and assessed the wetting properties of resultant SAMs. Substrates with Rrms either below or above the odd-even limit were investigated. With smoother surfaces (lower Rrms), an inverted asymmetric odd-even zigzag oscillation in static contact angles (θs) was observed with change from Au to Ag. Asymmetry in odd-even oscillation in Au was attributed to a larger change in θs from odd to even number of carbons in the n-alkanethiol and vice versa for Ag. For rougher surfaces, no odd-even effect was observed; however, a gradual increase in the static contact angle was observed. Increase in the average grain sizes (>3 times larger) on rough surfaces did not lead to significant difference in the wetting properties, suggesting that surface roughness significantly dominated the nature of the SAMs. We therefore infer that the predicted roughness-dependent limit to the observation of the odd-even effect in wetting properties of n-alkanethiols cannot be overcome by creating surfaces with large grain sizes for surfaces with Rrms > 1 nm. We also observed that the differences between Au and Ag surfaces are dominated by differences in the even-numbered SAMs, but this difference vanishes with shorter molecular chain length (≤C3).
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Affiliation(s)
- Zhengjia Wang
- Department of Materials Science and Engineering, Iowa State University , 2220 Hoover Hall, Ames, Iowa 50011 United States
| | - Jiahao Chen
- Department of Materials Science and Engineering, Iowa State University , 2220 Hoover Hall, Ames, Iowa 50011 United States
- Micro-Electronic Research Center, Iowa State University , 133 Applied Sciences Complex I, 1925 Scholl Road, Ames, Iowa 50011 United States
| | - Symon M Gathiaka
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego , Pharmaceutical Sciences Building, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Stephanie Oyola-Reynoso
- Department of Materials Science and Engineering, Iowa State University , 2220 Hoover Hall, Ames, Iowa 50011 United States
| | - Martin Thuo
- Department of Materials Science and Engineering, Iowa State University , 2220 Hoover Hall, Ames, Iowa 50011 United States
- Micro-Electronic Research Center, Iowa State University , 133 Applied Sciences Complex I, 1925 Scholl Road, Ames, Iowa 50011 United States
- Biopolymer and Biocomposites Research Team, Center for Bioplastics and Biocomposites, Iowa State University , 1041 Food Sciences Building, Ames, Iowa 50011 United States
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28
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Trasobares J, Vuillaume D, Théron D, Clément N. A 17 GHz molecular rectifier. Nat Commun 2016; 7:12850. [PMID: 27694833 PMCID: PMC5059435 DOI: 10.1038/ncomms12850] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 08/08/2016] [Indexed: 01/19/2023] Open
Abstract
Molecular electronics originally proposed that small molecules sandwiched between electrodes would accomplish electronic functions and enable ultimate scaling to be reached. However, so far, functional molecular devices have only been demonstrated at low frequency. Here, we demonstrate molecular diodes operating up to 17.8 GHz. Direct current and radio frequency (RF) properties were simultaneously measured on a large array of molecular junctions composed of gold nanocrystal electrodes, ferrocenyl undecanethiol molecules and the tip of an interferometric scanning microwave microscope. The present nanometre-scale molecular diodes offer a current density increase by several orders of magnitude compared with that of micrometre-scale molecular diodes, allowing RF operation. The measured S11 parameters show a diode rectification ratio of 12 dB which is linked to the rectification behaviour of the direct current conductance. From the RF measurements, we extrapolate a cut-off frequency of 520 GHz. A comparison with the silicon RF-Schottky diodes, architecture suggests that the RF-molecular diodes are extremely attractive for scaling and high-frequency operation. Molecular electronics holds promise to overcome scaling limits of conventional technologies, but is currently limited to low frequency operation. Here, Trasobares et al. show radio frequencies of up to 17.8 GHz in a molecular diode based on ferrocenyl undecanethiol self-assembled monolayers on gold nanodots.
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Affiliation(s)
- J Trasobares
- Institute of Electronics, Microelectronics and Nanotechnology, CNRS and University Lille 1, Physics Department, Avenue Poincaré, CS60069, 59652 Villeneuve d'Ascq, France
| | - D Vuillaume
- Institute of Electronics, Microelectronics and Nanotechnology, CNRS and University Lille 1, Physics Department, Avenue Poincaré, CS60069, 59652 Villeneuve d'Ascq, France
| | - D Théron
- Institute of Electronics, Microelectronics and Nanotechnology, CNRS and University Lille 1, Physics Department, Avenue Poincaré, CS60069, 59652 Villeneuve d'Ascq, France
| | - N Clément
- Institute of Electronics, Microelectronics and Nanotechnology, CNRS and University Lille 1, Physics Department, Avenue Poincaré, CS60069, 59652 Villeneuve d'Ascq, France.,NTT Basic Research Laboratories, NTT Corporation, 3-1, Morinosato Wakamiya, Atsugi-shi, Kanagawa 243-0198, Japan
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29
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Kumar S, van Herpt J, Gengler RYN, Feringa BL, Rudolf P, Chiechi RC. Mixed Monolayers of Spiropyrans Maximize Tunneling Conductance Switching by Photoisomerization at the Molecule-Electrode Interface in EGaIn Junctions. J Am Chem Soc 2016; 138:12519-26. [PMID: 27602432 PMCID: PMC5053170 DOI: 10.1021/jacs.6b06806] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Indexed: 01/19/2023]
Abstract
This paper describes the photoinduced switching of conductance in tunneling junctions comprising self-assembled monolayers of a spiropyran moiety using eutectic Ga-In top contacts. Despite separation of the spiropyran unit from the electrode by a long alkyl ester chain, we observe an increase in the current density J of a factor of 35 at 1 V when the closed form is irradiated with UV light to induce the ring-opening reaction, one of the highest switching ratios reported for junctions incorporating self-assembled monolayers. The magnitude of switching of hexanethiol mixed monolayers was higher than that of pure spiropyran monolayers. The first switching event recovers 100% of the initial value of J and in the mixed-monolayers subsequent dampening is not the result of degradation of the monolayer. The observation of increased conductivity is supported by zero-bias DFT calculations showing a change in the localization of the density of states near the Fermi level as well as by simulated transmission spectra revealing positive resonances that broaden and shift toward the Fermi level in the open form.
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Affiliation(s)
- Sumit Kumar
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Jochem
T. van Herpt
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Régis Y. N. Gengler
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Ben L. Feringa
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Petra Rudolf
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Ryan C. Chiechi
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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30
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Morteza Najarian A, Szeto B, Tefashe UM, McCreery RL. Robust All-Carbon Molecular Junctions on Flexible or Semi-Transparent Substrates Using "Process-Friendly" Fabrication. ACS NANO 2016; 10:8918-8928. [PMID: 27529117 DOI: 10.1021/acsnano.6b04900] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Large area molecular junctions were fabricated on electron-beam deposited carbon (eC) surfaces with molecular layers in the range of 2-5.5 nm between conducting, amorphous carbon contacts. Incorporating eC as an interconnect between Au and the molecular layer improves substrate roughness, prevents electromigration and uses well-known electrochemistry to form a covalent C-C bond to the molecular layer. Au/eC/anthraquinone/eC/Au junctions were fabricated on Si/SiOx with high yield and reproducibility and were unchanged by 10(7) current-voltage cycles and temperatures between 80 and 450 K. Au/eC/AQ/eC/Au devices fabricated on plastic films were unchanged by 10(7) current density vs bias voltage (J-V) cycles and repeated bending of the entire assembled junction. The low sheet resistance of Au/eC substrates permitted junctions with sufficiently transparent electrodes to conduct Raman or UV-vis absorption spectroscopy in either reflection or transmission geometries. Lithographic patterning of Au/eC substrates permitted wafer-scale integration yielding 500 devices on 20 chips on a 100 mm diameter wafer. Collectively, eC on Au provides a platform for fabrication and operation of chemically stable, optically and electrically functional molecules on rigid or flexible materials. The relative ease of processing and the robustness of molecular junctions incorporating eC layers should help address the challenge of economic fabrication of practical, flexible molecular junctions for a potentially wide range of applications.
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Affiliation(s)
- Amin Morteza Najarian
- Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2R3, Canada
- National Institute for Nanotechnology, National Research Council Canada , Edmonton, Alberta T6G 2G2, Canada
| | - Bryan Szeto
- National Institute for Nanotechnology, National Research Council Canada , Edmonton, Alberta T6G 2G2, Canada
| | - Ushula M Tefashe
- Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2R3, Canada
- National Institute for Nanotechnology, National Research Council Canada , Edmonton, Alberta T6G 2G2, Canada
| | - Richard L McCreery
- Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2R3, Canada
- National Institute for Nanotechnology, National Research Council Canada , Edmonton, Alberta T6G 2G2, Canada
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31
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Bayat A, Lacroix JC, McCreery RL. Control of Electronic Symmetry and Rectification through Energy Level Variations in Bilayer Molecular Junctions. J Am Chem Soc 2016; 138:12287-96. [DOI: 10.1021/jacs.6b07499] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Akhtar Bayat
- University of Alberta, 11421 Saskatchewan
Drive, Edmonton, Alberta T6G 2M9, Canada
| | - Jean-Christophe Lacroix
- Université Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR
7086 CNRS, 15 rue Jean-Antoine de Baïf, 75205 Paris Cedex 13, France
| | - Richard L. McCreery
- University of Alberta, 11421 Saskatchewan
Drive, Edmonton, Alberta T6G 2M9, Canada
- National Institute for Nanotechnology, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
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32
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Garrigues AR, Wang L, Del Barco E, Nijhuis CA. Electrostatic control over temperature-dependent tunnelling across a single-molecule junction. Nat Commun 2016; 7:11595. [PMID: 27211787 PMCID: PMC4879245 DOI: 10.1038/ncomms11595] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 04/12/2016] [Indexed: 01/20/2023] Open
Abstract
Understanding how the mechanism of charge transport through molecular tunnel junctions depends on temperature is crucial to control electronic function in molecular electronic devices. With just a few systems investigated as a function of bias and temperature so far, thermal effects in molecular tunnel junctions remain poorly understood. Here we report a detailed charge transport study of an individual redox-active ferrocene-based molecule over a wide range of temperatures and applied potentials. The results show the temperature dependence of the current to vary strongly as a function of the gate voltage. Specifically, the current across the molecule exponentially increases in the Coulomb blockade regime and decreases at the charge degeneracy points, while remaining temperature-independent at resonance. Our observations can be well accounted for by a formal single-level tunnelling model where the temperature dependence relies on the thermal broadening of the Fermi distributions of the electrons in the leads.
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Affiliation(s)
- Alvar R Garrigues
- Department of Physics, University of Central Florida, Orlando, Florida 32816, USA
| | - Lejia Wang
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Enrique Del Barco
- Department of Physics, University of Central Florida, Orlando, Florida 32816, USA
| | - Christian A Nijhuis
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.,Centre for Advanced 2D Materials, National University of Singapore, 6 Science Drive 2, Singapore 117546, Singapore
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33
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Jang Y, Jeong H, Kim D, Hwang WT, Kim JW, Jeong I, Song H, Yoon J, Yi GC, Jeong H, Lee T. Electrical characterization of benzenedithiolate molecular electronic devices with graphene electrodes on rigid and flexible substrates. NANOTECHNOLOGY 2016; 27:145301. [PMID: 26902885 DOI: 10.1088/0957-4484/27/14/145301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We investigated the electrical characteristics of molecular electronic devices consisting of benzenedithiolate self-assembled monolayers and a graphene electrode. We used the multilayer graphene electrode as a protective interlayer to prevent filamentary path formation during the evaporation of the top electrode in the vertical metal-molecule-metal junction structure. The devices were fabricated both on a rigid SiO2/Si substrate and on a flexible poly(ethylene terephthalate) substrate. Using these devices, we investigated the basic charge transport characteristics of benzenedithiolate molecular junctions in length- and temperature-dependent analyses. Additionally, the reliability of the electrical characteristics of the flexible benzenedithiolate molecular devices was investigated under various mechanical bending conditions, such as different bending radii, repeated bending cycles, and a retention test under bending. We also observed the inelastic electron tunneling spectra of our fabricated graphene-electrode molecular devices. Based on the results, we verified that benzenedithiolate molecules participate in charge transport, serving as an active tunneling barrier in solid-state graphene-electrode molecular junctions.
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Affiliation(s)
- Yeonsik Jang
- Department of Physics and Astronomy, and Institute of Applied Physics, Seoul National University, Seoul 08826, Korea
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34
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Photoresponse of supramolecular self-assembled networks on graphene-diamond interfaces. Nat Commun 2016; 7:10700. [PMID: 26911248 PMCID: PMC4773422 DOI: 10.1038/ncomms10700] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/14/2016] [Indexed: 11/17/2022] Open
Abstract
Nature employs self-assembly to fabricate the most complex molecularly precise machinery known to man. Heteromolecular, two-dimensional self-assembled networks provide a route to spatially organize different building blocks relative to each other, enabling synthetic molecularly precise fabrication. Here we demonstrate optoelectronic function in a near-to-monolayer molecular architecture approaching atomically defined spatial disposition of all components. The active layer consists of a self-assembled terrylene-based dye, forming a bicomponent supramolecular network with melamine. The assembly at the graphene-diamond interface shows an absorption maximum at 740 nm whereby the photoresponse can be measured with a gallium counter electrode. We find photocurrents of 0.5 nA and open-circuit voltages of 270 mV employing 19 mW cm−2 irradiation intensities at 710 nm. With an ex situ calculated contact area of 9.9 × 102 μm2, an incident photon to current efficiency of 0.6% at 710 nm is estimated, opening up intriguing possibilities in bottom-up optoelectronic device fabrication with molecular resolution. Two-dimensional, self-assembled heteromolecular networks often lack functionality. Here the authors study the photoresponse of self-assembled heteromolecular networks, while controlling their positions and interfaces at an atomic level, suggesting bottom-up assembly of optoelectronics devices.
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35
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Garrigues AR, Yuan L, Wang L, Singh S, del Barco E, Nijhuis CA. Temperature dependent charge transport across tunnel junctions of single-molecules and self-assembled monolayers: a comparative study. Dalton Trans 2016; 45:17153-17159. [PMID: 27775126 DOI: 10.1039/c6dt03204d] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
In this work we present a comparative study of the temperature behavior of charge current in both single-molecule transistors and self-assembled monolayer-based tunnel junctions with ferrocene molecules.
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Affiliation(s)
| | - Li Yuan
- Department of Chemistry
- National University of Singapore
- Singapore 117543
- Singapore
| | - Lejia Wang
- Department of Chemistry
- National University of Singapore
- Singapore 117543
- Singapore
- School of Chemical Engineering
| | | | | | - Christian A. Nijhuis
- Department of Chemistry
- National University of Singapore
- Singapore 117543
- Singapore
- Centre for Advanced 2D Materials
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36
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Revisiting the Challenges in Fabricating Uniform Coatings with Polyfunctional Molecules on High Surface Energy Materials. COATINGS 2015. [DOI: 10.3390/coatings5041002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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37
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Wan A, Suchand Sangeeth CS, Wang L, Yuan L, Jiang L, Nijhuis CA. Arrays of high quality SAM-based junctions and their application in molecular diode based logic. NANOSCALE 2015; 7:19547-56. [PMID: 26537895 DOI: 10.1039/c5nr05533d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
This paper describes a method to fabricate a microfluidic top-electrode that can be utilized to generate arrays of self-assembled monolayer (SAM)-based junctions. The top-electrodes consist of a liquid-metal of GaOx/EGaIn mechanically stabilized in microchannels and through-holes in polydimethylsiloxane (PDMS); these top-electrodes form molecular junctions by directly placing them onto the SAM supported by template-stripped (TS) Ag or Au bottom-electrodes. Unlike conventional techniques to form multiple junctions, our method does not require lithography to pattern the bottom-electrode and is compatible with TS bottom-electrodes, which are ultra-flat with large grains, free from potential contamination of photoresist residues, and do not have electrode-edges where the molecules are unable to pack well. We formed tunneling junctions with n-alkanethiolate SAMs in yields of ∼80%, with good reproducibility and electrical stability. Temperature dependent J(V) measurements indicated that the mechanism of charge transport across the junction is coherent tunneling. To demonstrate the usefulness of these junctions, we formed molecular diodes based on SAMs with Fc head groups. These junctions rectify currents with a rectification ratio R of 45. These molecular diodes were incorporated in simple electronic circuitry to demonstrate molecular diode-based Boolean logic.
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Affiliation(s)
- Albert Wan
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
| | - C S Suchand Sangeeth
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
| | - Lejia Wang
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
| | - Li Yuan
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
| | - Li Jiang
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
| | - Christian A Nijhuis
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore. and Solar Energy Research Institute of Singapore (SERIS), 7 Engineering Drive 1 and National University of Singapore, Singapore 117574, Singapore
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38
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39
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Balgley R, Shankar S, Lahav M, van der Boom ME. Rerouting Electron Transfer in Molecular Assemblies by Redox-Pair Matching. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201505290] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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40
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Balgley R, Shankar S, Lahav M, van der Boom ME. Rerouting Electron Transfer in Molecular Assemblies by Redox-Pair Matching. Angew Chem Int Ed Engl 2015; 54:12457-62. [DOI: 10.1002/anie.201505290] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 08/06/2015] [Indexed: 11/06/2022]
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41
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Castañeda Ocampo OE, Gordiichuk P, Catarci S, Gautier DA, Herrmann A, Chiechi RC. Mechanism of Orientation-Dependent Asymmetric Charge Transport in Tunneling Junctions Comprising Photosystem I. J Am Chem Soc 2015; 137:8419-27. [PMID: 26057523 PMCID: PMC4558993 DOI: 10.1021/jacs.5b01241] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recently, photoactive proteins have gained a lot of attention due to their incorporation into bioinspired (photo)electrochemical and solar cells. This paper describes the measurement of the asymmetry of current transport of self-assembled monolayers (SAMs) of the entire photosystem I (PSI) protein complex (not the isolated reaction center, RCI), on two different "director SAMs" supported by ultraflat Au substrates. The director SAMs induce the preferential orientation of PSI, which manifest as asymmetry in tunneling charge-transport. We measured the oriented SAMs of PSI using eutectic Ga-In (EGaIn), a large-area technique, and conducting probe atomic force microscopy (CP-AFM), a single-complex technique, and determined that the transport properties are comparable. By varying the temperatures at which the measurements were performed, we found that there is no measurable dependence of the current on temperature from ±0.1 to ±1.0 V bias, and thus, we suggest tunneling as the mechanism for transport; there are no thermally activated (e.g., hopping) processes. Therefore, it is likely that relaxation in the electron transport chain is not responsible for the asymmetry in the conductance of SAMs of PSI complexes in these junctions, which we ascribe instead to the presence of a large, net dipole moment present in PSI.
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Affiliation(s)
- Olga E Castañeda Ocampo
- †Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.,‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Pavlo Gordiichuk
- ‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Stefano Catarci
- ‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Daniel A Gautier
- ‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Andreas Herrmann
- ‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Ryan C Chiechi
- †Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.,‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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42
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Affiliation(s)
- Robert M. Metzger
- Laboratory for Molecular
Electronics, Department of Chemistry, The University of Alabama, Box 870336, Tuscaloosa, Alabama 35487-0336, United States
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43
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Controlling the direction of rectification in a molecular diode. Nat Commun 2015; 6:6324. [DOI: 10.1038/ncomms7324] [Citation(s) in RCA: 165] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 01/18/2015] [Indexed: 02/06/2023] Open
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44
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Miller MS, Ferrato MA, Niec A, Biesinger MC, Carmichael TB. Ultrasmooth gold surfaces prepared by chemical mechanical polishing for applications in nanoscience. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:14171-14178. [PMID: 25372513 DOI: 10.1021/la5032027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
For over 20 years, template stripping has been the best method for preparing ultrasmooth metal surfaces for studies of nanostructures. However, the organic adhesives used in the template stripping method are incompatible with many solvents, limiting the conditions that may subsequently be used to prepare samples; in addition, the film areas that can be reliably prepared are typically limited to ∼1 cm(2). In this article, we present chemical-mechanical polishing (CMP) as an adhesive-free, scalable method of preparing ultrasmooth gold surfaces. In this process, a gold film is first deposited by e-beam evaporation onto a 76-mm-diameter silicon wafer. The CMP process removes ∼4 nm of gold from the tops of the grains comprising the gold film to produce an ultrasmooth gold surface supported on the silicon wafer. We measured root-mean-square (RMS) roughness values using atomic force microscopy of 12 randomly sampled 1 μm × 1 μm areas on the surface of the wafer and repeated the process on 5 different CMP wafers. The average RMS roughness was 3.8 ± 0.5 Å, which is comparable to measured values for template-stripped gold (3.7 ± 0.5 Å). We also compared the use of CMP and template-stripped gold as bottom electrical contacts in molecular electronic junctions formed from n-alkanethiolate self-assembled monolayers as a sensitive test bed to detect differences in the topography of the gold surfaces. We demonstrate that these substrates produce statistically indistinguishable values for the tunneling decay coefficient β, which is highly sensitive to the gold surface topography.
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Affiliation(s)
- Michael S Miller
- Department of Chemistry and Biochemistry, University of Windsor , Windsor, Ontario, Canada N9B 3P4
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45
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Wimbush KS, Fratila RM, Wang D, Qi D, Liang C, Yuan L, Yakovlev N, Loh KP, Reinhoudt DN, Velders AH, Nijhuis CA. Bias induced transition from an ohmic to a non-ohmic interface in supramolecular tunneling junctions with Ga2O3/EGaIn top electrodes. NANOSCALE 2014; 6:11246-58. [PMID: 25132523 DOI: 10.1039/c4nr02933j] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
This study describes that the current rectification ratio, R ≡ |J|(-2.0 V)/|J|(+2.0 V) for supramolecular tunneling junctions with a top-electrode of eutectic gallium indium (EGaIn) that contains a conductive thin (0.7 nm) supporting outer oxide layer (Ga2O3), increases by up to four orders of magnitude under an applied bias of >+1.0 V up to +2.5 V; these junctions did not change their electrical characteristics when biased in the voltage range of ±1.0 V. The increase in R is caused by the presence of water and ions in the supramolecular assemblies which react with the Ga2O3/EGaIn layer and increase the thickness of the Ga2O3 layer. This increase in the oxide thickness from 0.7 nm to ∼2.0 nm changed the nature of the monolayer-top-electrode contact from an ohmic to a non-ohmic contact. These results unambiguously expose the experimental conditions that allow for a safe bias window of ±1.0 V (the range of biases studies of charge transport using this technique are normally conducted) to investigate molecular effects in molecular electronic junctions with Ga2O3/EGaIn top-electrodes where electrochemical reactions are not significant. Our findings also show that the interpretation of data in studies involving applied biases of >1.0 V may be complicated by electrochemical side reactions which can be recognized by changes of the electrical characteristics as a function voltage cycling or in current retention experiments.
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Affiliation(s)
- Kim S Wimbush
- Laboratory of Supramolecular Chemistry and Technology, MESA + Research Institute, University of Twente, 7500 AE Enschede, The Netherlands.
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46
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Kumar V, Giri SK, Venugopalan P, Kartha KPR. Synthesis of Cross-Linked Glycopeptides and Ureas by a Mechanochemical, Solvent-Free Reaction and Determination of Their Structural Properties by TEM and X-ray Crystallography. Chempluschem 2014. [DOI: 10.1002/cplu.201402185] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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47
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Sangeeth CSS, Wan A, Nijhuis CA. Equivalent Circuits of a Self-Assembled Monolayer-Based Tunnel Junction Determined by Impedance Spectroscopy. J Am Chem Soc 2014; 136:11134-44. [DOI: 10.1021/ja505420c] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- C. S. Suchand Sangeeth
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
| | - Albert Wan
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
| | - Christian A. Nijhuis
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
- Graphene Research
Centre, National University of Singapore, 2 Science Drive 3, Singapore 117542
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Kim D, Jeong H, Lee H, Hwang WT, Wolf J, Scheer E, Huhn T, Jeong H, Lee T. Flexible molecular-scale electronic devices composed of diarylethene photoswitching molecules. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2014; 26:3968-3973. [PMID: 24687399 DOI: 10.1002/adma.201306316] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 02/21/2014] [Indexed: 06/03/2023]
Affiliation(s)
- Dongku Kim
- Department of Physics and Astronomy and Institute of Applied Physics, Seoul National University, Seoul, 151-747, Korea
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Bowers CM, Liao KC, Yoon HJ, Rappoport D, Baghbanzadeh M, Simeone FC, Whitesides GM. Introducing ionic and/or hydrogen bonds into the SAM//Ga2O3 top-interface of Ag(TS)/S(CH2)nT//Ga2O3/EGaIn junctions. NANO LETTERS 2014; 14:3521-3526. [PMID: 24840009 DOI: 10.1021/nl501126e] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Junctions with the structure Ag(TS)/S(CH2)nT//Ga2O3/EGaIn (where S(CH2)nT is a self-assembled monolayer, SAM, of n-alkanethiolate bearing a terminal functional group T) make it possible to examine the response of rates of charge transport by tunneling to changes in the strength of the interaction between T and Ga2O3. Introducing a series of Lewis acidic/basic functional groups (T = -OH, -SH, -CO2H, -CONH2, and -PO3H) at the terminus of the SAM gave values for the tunneling current density, J(V) in A/cm(2), that were indistinguishable (i.e., differed by less than a factor of 3) from the values observed with n-alkanethiolates of equivalent length. The insensitivity of the rate of tunneling to changes in the terminal functional group implies that replacing weak van der Waals contact interactions with stronger hydrogen- or ionic bonds at the T//Ga2O3 interface does not change the shape (i.e., the height or width) of the tunneling barrier enough to affect rates of charge transport. A comparison of the injection current, J0, for T = -CO2H, and T = -CH2CH3--two groups having similar extended lengths (in Å, or in numbers of non-hydrogen atoms)--suggests that both groups make indistinguishable contributions to the height of the tunneling barrier.
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Affiliation(s)
- Carleen M Bowers
- Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States
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Zhang Y, Zhao Z, Fracasso D, Chiechi RC. Bottom-Up Molecular Tunneling Junctions Formed by Self-Assembly. Isr J Chem 2014. [DOI: 10.1002/ijch.201400033] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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