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Tan M, Sun F, Zhao X, Zhao Z, Zhang S, Xu X, Adijiang A, Zhang W, Wang H, Wang C, Li Z, Scheer E, Xiang D. Conductance Evolution of Photoisomeric Single-Molecule Junctions under Ultraviolet Irradiation and Mechanical Stretching. J Am Chem Soc 2024; 146:6856-6865. [PMID: 38413090 DOI: 10.1021/jacs.3c13752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
A comprehensive understanding of carrier transport in photoisomeric molecular junctions is crucial for the rational design and delicate fabrication of single-molecule functional devices. It has been widely recognized that the conductance of azobenzene (a class of photoisomeric molecules) based molecular junctions is mainly determined by photoinduced conformational changes. In this study, it is demonstrated that the most probable conductance of amine-anchored azobenzene-based molecular junctions increases continuously upon UV irradiation. In contrast, the conductance of pyridyl-anchored molecular junctions with an identical azobenzene core exhibits a contrasting trend, highlighting the pivotal role that anchoring groups play, potentially overriding (even reversing) the effects of photoinduced conformational changes. It is further demonstrated that the molecule with cis-conformation cannot be fully mechanically stretched into the trans-conformation, clarifying that it is a great challenge to realize a reversible molecular switch by purely mechanical operation. Additionally, it is revealed that the coupling strength of pyridyl-anchored molecules is dramatically weakened when the UV irradiation time is prolonged, whereas it is not observed for amine-anchored molecules. The mechanisms for these observations are elucidated with the assistance of density functional theory calculations and UV-Vis spectra combined with flicker noise measurements which confirm the photoinduced conformational changes, providing insight into understanding the charge transport in photoisomeric molecular junctions and offering a routine for logical designing synchro opto-mechanical molecular switches.
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Affiliation(s)
- Min Tan
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin 300350, China
| | - Feng Sun
- Key Laboratory of Medical Physics and Image Processing of Shandong Province, School of Physics and Electronics, Shandong Normal University, Jinan, Shandong 250358, China
| | - Xueyan Zhao
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin 300350, China
| | - Zhibin Zhao
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin 300350, China
| | - Surong Zhang
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin 300350, China
| | - Xiaona Xu
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin 300350, China
| | - Adila Adijiang
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin 300350, China
| | - Wei Zhang
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin 300350, China
| | - Haoyu Wang
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin 300350, China
| | - Chuankui Wang
- Key Laboratory of Medical Physics and Image Processing of Shandong Province, School of Physics and Electronics, Shandong Normal University, Jinan, Shandong 250358, China
| | - Zongliang Li
- Key Laboratory of Medical Physics and Image Processing of Shandong Province, School of Physics and Electronics, Shandong Normal University, Jinan, Shandong 250358, China
| | - Elke Scheer
- Department of Physics, University of Konstanz, Konstanz 78457, Germany
| | - Dong Xiang
- Institute of Modern Optics and Center of Single-Molecule Science, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin 300350, China
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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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Hnid I, Yassin A, Arbouch I, Guérin D, van Dyck C, Sanguinet L, Lenfant S, Cornil J, Blanchard P, Vuillaume D. Molecular Junctions for Terahertz Switches and Detectors. NANO LETTERS 2024; 24:2553-2560. [PMID: 38363554 DOI: 10.1021/acs.nanolett.3c04602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Molecular electronics targets tiny devices exploiting the electronic properties of the molecular orbitals, which can be tailored and controlled by the chemical structure and configuration of the molecules. Many functional devices have been experimentally demonstrated; however, these devices were operated in the low-frequency domain (mainly dc to MHz). This represents a serious limitation for electronic applications, although molecular devices working in the THz regime have been theoretically predicted. Here, we experimentally demonstrate molecular THz switches at room temperature. The devices consist of self-assembled monolayers of molecules bearing two conjugated moieties coupled through a nonconjugated linker. These devices exhibit clear negative differential conductance behaviors (peaks in the current-voltage curves), as confirmed by ab initio simulations, which were reversibly suppressed under illumination with a 30 THz wave. We analyze how the THz switching behavior depends on the THz wave properties (power and frequency), and we benchmark that these molecular devices would outperform actual THz detectors.
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Affiliation(s)
- Imen Hnid
- Institute for Electronics Microelectronics and Nanotechnology (IEMN), CNRS, University of Lille, Av. Poincaré, F-59652 Villeneuve d'Ascq, France
| | - Ali Yassin
- MOLTECH-Anjou, CNRS, University of Angers, SFR MATRIX, F-49000 Angers, France
- Natural Sciences Department, School of Arts and Sciences, Lebanese American University, 1102-2801, Beirut, Lebanon
| | - Imane Arbouch
- Laboratory for Chemistry of Novel Materials, University of Mons, 7000 Mons, Belgium
| | - David Guérin
- Institute for Electronics Microelectronics and Nanotechnology (IEMN), CNRS, University of Lille, Av. Poincaré, F-59652 Villeneuve d'Ascq, France
| | - Colin van Dyck
- Theoretical Chemical Physics group, University of Mons, 7000 Mons, Belgium
| | - Lionel Sanguinet
- MOLTECH-Anjou, CNRS, University of Angers, SFR MATRIX, F-49000 Angers, France
| | - Stéphane Lenfant
- Institute for Electronics Microelectronics and Nanotechnology (IEMN), CNRS, University of Lille, Av. Poincaré, F-59652 Villeneuve d'Ascq, France
| | - Jérôme Cornil
- Laboratory for Chemistry of Novel Materials, University of Mons, 7000 Mons, Belgium
| | - Philippe Blanchard
- MOLTECH-Anjou, CNRS, University of Angers, SFR MATRIX, F-49000 Angers, France
| | - Dominique Vuillaume
- Institute for Electronics Microelectronics and Nanotechnology (IEMN), CNRS, University of Lille, Av. Poincaré, F-59652 Villeneuve d'Ascq, France
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4
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Reimers JR, Li T, Birvé AP, Yang L, Aragonès AC, Fallon T, Kosov DS, Darwish N. Controlling piezoresistance in single molecules through the isomerisation of bullvalenes. Nat Commun 2023; 14:6089. [PMID: 37789027 PMCID: PMC10547723 DOI: 10.1038/s41467-023-41674-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 09/06/2023] [Indexed: 10/05/2023] Open
Abstract
Nanoscale electro-mechanical systems (NEMS) displaying piezoresistance offer unique measurement opportunities at the sub-cellular level, in detectors and sensors, and in emerging generations of integrated electronic devices. Here, we show a single-molecule NEMS piezoresistor that operates utilising constitutional and conformational isomerisation of individual diaryl-bullvalene molecules and can be switched at 850 Hz. Observations are made using scanning tunnelling microscopy break junction (STMBJ) techniques to characterise piezoresistance, combined with blinking (current-time) experiments that follow single-molecule reactions in real time. A kinetic Monte Carlo methodology (KMC) is developed to simulate isomerisation on the experimental timescale, parameterised using density-functional theory (DFT) combined with non-equilibrium Green's function (NEGF) calculations. Results indicate that piezoresistance is controlled by both constitutional and conformational isomerisation, occurring at rates that are either fast (equilibrium) or slow (non-equilibrium) compared to the experimental timescale. Two different types of STMBJ traces are observed, one typical of traditional experiments that are interpreted in terms of intramolecular isomerisation occurring on stable tipped-shaped metal-contact junctions, and another attributed to arise from junction‒interface restructuring induced by bullvalene isomerisation.
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Affiliation(s)
- Jeffrey R Reimers
- International Centre for Quantum and Molecular Structures and the Department of Physics, Shanghai University, Shanghai, 200444, China.
- School of Mathematical and Physical Sciences, University of Technology Sydney, Sydney, NSW, 2007, Australia.
| | - Tiexin Li
- School of Molecular and Life Sciences, Curtin University, Bentley, WA, 6102, Australia
| | - André P Birvé
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Likun Yang
- International Centre for Quantum and Molecular Structures and the Department of Physics, Shanghai University, Shanghai, 200444, China
| | - Albert C Aragonès
- Department of Materials Science and Physical Chemistry, University of Barcelona, Marti i Franquès 1, 08028, Barcelona, Catalonia, Spain
- Institute of Theoretical and Computational Chemistry, University of Barcelona, Diagonal 645, 08028, Barcelona, Catalonia, Spain
| | - Thomas Fallon
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW, 2308, Australia.
| | - Daniel S Kosov
- College of Science and Engineering, James Cook University, Townsville, QLD, 4811, Australia.
| | - Nadim Darwish
- School of Molecular and Life Sciences, Curtin University, Bentley, WA, 6102, Australia.
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5
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Madrid I, Zheng Z, Gerbelot C, Fujiwara A, Li S, Grall S, Nishiguchi K, Kim SH, Chovin A, Demaille C, Clement N. Ballistic Brownian Motion of Nanoconfined DNA. ACS NANO 2023; 17:17031-17040. [PMID: 37700490 DOI: 10.1021/acsnano.3c04349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/14/2023]
Abstract
Theoretical treatments of polymer dynamics in liquid generally start with the basic assumption that motion at the smallest scale is heavily overdamped; therefore, inertia can be neglected. We report on the Brownian motion of tethered DNA under nanoconfinement, which was analyzed by molecular dynamics simulation and nanoelectrochemistry-based single-electron shuttle experiments. Our results show a transition into the ballistic Brownian motion regime for short DNA in sub-5 nm gaps, with quality coefficients as high as 2 for double-stranded DNA, an effect mainly attributed to a drastic increase in stiffness. The possibility for DNA to enter the underdamped regime could have profound implications on our understanding of the energetics of biomolecular engines such as the replication machinery, which operates in nanocavities that are a few nanometers wide.
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Affiliation(s)
- Ignacio Madrid
- IIS, LIMMS CNRS-IIS UMI2820, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo 153-8505, Japan
| | - Zhiyong Zheng
- Laboratoire d'Electrochimie Moléculaire, UMR 7591 CNRS, Université Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| | - Cedric Gerbelot
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi-shi 243-0198, Japan
| | - Akira Fujiwara
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi-shi 243-0198, Japan
| | - Shuo Li
- IIS, LIMMS CNRS-IIS UMI2820, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo 153-8505, Japan
| | - Simon Grall
- IIS, LIMMS CNRS-IIS UMI2820, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo 153-8505, Japan
| | - Katsuhiko Nishiguchi
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi-shi 243-0198, Japan
| | - Soo Hyeon Kim
- IIS, LIMMS CNRS-IIS UMI2820, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo 153-8505, Japan
| | - Arnaud Chovin
- Laboratoire d'Electrochimie Moléculaire, UMR 7591 CNRS, Université Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| | - Christophe Demaille
- Laboratoire d'Electrochimie Moléculaire, UMR 7591 CNRS, Université Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| | - Nicolas Clement
- IIS, LIMMS CNRS-IIS UMI2820, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo 153-8505, Japan
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi-shi 243-0198, Japan
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6
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Li S, Coffinier Y, Lagadec C, Cleri F, Nishiguchi K, Fujiwara A, Kim SH, Clément N. Single-Cell Electrochemical Aptasensor Array. ACS Sens 2023; 8:2921-2926. [PMID: 37431846 DOI: 10.1021/acssensors.3c00570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/12/2023]
Abstract
Despite several demonstrations of electrochemical devices with limits of detection (LOD) of 1 cell/mL, the implementation of single-cell bioelectrochemical sensor arrays has remained elusive due to the challenges of scaling up. In this study, we show that the recently introduced nanopillar array technology combined with redox-labeled aptamers targeting epithelial cell adhesion molecule (EpCAM) is perfectly suited for such implementation. Combining nanopillar arrays with microwells determined for single cell trapping directly on the sensor surface, single target cells are successfully detected and analyzed. This first implementation of a single-cell electrochemical aptasensor array, based on Brownian-fluctuating redox species, opens new opportunities for large-scale implementation and statistical analysis of early cancer diagnosis and cancer therapy in clinical settings.
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Affiliation(s)
- Shuo Li
- IIS, LIMMS/CNRS-IIS IRL2820, The Univ. of Tokyo 4-6-1 Komaba, Meguro-ku 153-8505, Tokyo, Japan
| | - Yannick Coffinier
- IEMN, CNRS UMR8520, Univ. Lille Avenue Poincare, BP 60069, Villeneuve d'Ascq cedex 59652, France
| | - Chann Lagadec
- Univ. Lille, CNRS, Inserm, CHU Lille, Centre Oscar Lambret, UMR9020 - UMR-S 1277 - Canther - Cancer Heterogeneity, Plasticity and Resistance to Therapies, Lille F-59000, France
| | - Fabrizio Cleri
- IEMN, CNRS UMR8520, Univ. Lille Avenue Poincare, BP 60069, Villeneuve d'Ascq cedex 59652, France
| | - Katsuhiko Nishiguchi
- NTT Basic Research Laboratories, NTT Corporation, 3-1, Morinosato-Wakamiya, Atsugi-shi 243-0198, Japan
| | - Akira Fujiwara
- NTT Basic Research Laboratories, NTT Corporation, 3-1, Morinosato-Wakamiya, Atsugi-shi 243-0198, Japan
| | - Soo Hyeon Kim
- IIS, LIMMS/CNRS-IIS IRL2820, The Univ. of Tokyo 4-6-1 Komaba, Meguro-ku 153-8505, Tokyo, Japan
| | - Nicolas Clément
- IIS, LIMMS/CNRS-IIS IRL2820, The Univ. of Tokyo 4-6-1 Komaba, Meguro-ku 153-8505, Tokyo, Japan
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7
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Lokamani M, Kilibarda F, Günther F, Kelling J, Strobel A, Zahn P, Juckeland G, Gothelf KV, Scheer E, Gemming S, Erbe A. Stretch Evolution of Electronic Coupling of the Thiophenyl Anchoring Group with Gold in Mechanically Controllable Break Junctions. J Phys Chem Lett 2023:5709-5717. [PMID: 37318265 DOI: 10.1021/acs.jpclett.3c00370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The current-voltage characteristics of a single-molecule junction are determined by the electronic coupling Γ between the electronic states of the electrodes and the dominant transport channel(s) of the molecule. Γ is profoundly affected by the choice of the anchoring groups and their binding positions on the tip facets and the tip-tip separation. In this work, mechanically controllable break junction experiments on the N,N'-bis(5-ethynylbenzenethiol-salicylidene)ethylenediamine are presented, in particular, the stretch evolution of Γ with increasing tip-tip separation. The stretch evolution of Γ is characterized by recurring local maxima and can be related to the deformation of the molecule and sliding of the anchoring groups above the tip facets and along the tip edges. A dynamic simulation approach is implemented to model the stretch evolution of Γ, which captures the experimentally observed features remarkably well and establishes a link to the microscopic structure of the single-molecule junction.
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Affiliation(s)
- Mani Lokamani
- Department of Information Services and Computing, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, 01328 Dresden, Germany
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, 01328 Dresden, Germany
| | - Filip Kilibarda
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, 01328 Dresden, Germany
| | - Florian Günther
- Instituto de Física de São Carlos, Universidade de São Paulo, USP Av. Trabalhador saocarlense, 400, 13560-970, São Carlos, São Paulo, Brazil
| | - Jeffrey Kelling
- Department of Information Services and Computing, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, 01328 Dresden, Germany
- Institute of Physics, Technische Universität Chemnitz, 09107 Chemnitz, Germany
| | - Alexander Strobel
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, 01328 Dresden, Germany
| | - Peter Zahn
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, 01328 Dresden, Germany
| | - Guido Juckeland
- Department of Information Services and Computing, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, 01328 Dresden, Germany
| | - Kurt V Gothelf
- Department of Chemistry and Interdisciplinary Nanoscience Center, Centre for DNA Nanotechnology, iNANO, Gustav Wieds Vej 14, Aarhus C, 8000 Denmark
| | - Elke Scheer
- Department of Physics, University of Konstanz, 78457 Konstanz, Germany
| | - Sibylle Gemming
- Institute of Physics, Technische Universität Chemnitz, 09107 Chemnitz, Germany
| | - Artur Erbe
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, 01328 Dresden, Germany
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8
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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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9
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Grall S, Li S, Jalabert L, Kim SH, Chovin A, Demaille C, Clément N. Electrochemical Shot Noise of a Redox Monolayer. PHYSICAL REVIEW LETTERS 2023; 130:218001. [PMID: 37295112 DOI: 10.1103/physrevlett.130.218001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 04/25/2023] [Indexed: 06/12/2023]
Abstract
Redox monolayers are the base for a wide variety of devices including high-frequency molecular diodes or biomolecular sensors. We introduce a formalism to describe the electrochemical shot noise of such a monolayer, confirmed experimentally at room temperature in liquid. The proposed method, carried out at equilibrium, avoids parasitic capacitance, increases the sensitivity, and allows us to obtain quantitative information such as the electronic coupling (or standard electron transfer rates), its dispersion, and the number of molecules. Unlike in solid-state physics, the homogeneity in energy levels and transfer rates in the monolayer yields a Lorentzian spectrum. This first step for shot noise studies in molecular electrochemical systems opens perspectives for quantum transport studies in a liquid environment at room temperature as well as highly sensitive measurements for bioelectrochemical sensors.
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Affiliation(s)
- Simon Grall
- IIS, LIMMS/CNRS-IIS IRL2820, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo, 153-8505, Japan
| | - Shuo Li
- IIS, LIMMS/CNRS-IIS IRL2820, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo, 153-8505, Japan
| | - Laurent Jalabert
- IIS, LIMMS/CNRS-IIS IRL2820, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo, 153-8505, Japan
| | - Soo Hyeon Kim
- IIS, LIMMS/CNRS-IIS IRL2820, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo, 153-8505, Japan
| | - Arnaud Chovin
- Université Paris Cité, CNRS, Laboratoire d'Electrochimie Moléculaire, F-75013 Paris, France
| | - Christophe Demaille
- Université Paris Cité, CNRS, Laboratoire d'Electrochimie Moléculaire, F-75013 Paris, France
| | - Nicolas Clément
- IIS, LIMMS/CNRS-IIS IRL2820, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo, 153-8505, Japan
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10
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Li X, Ge W, Guo S, Bai J, Hong W. Characterization and Application of Supramolecular Junctions. Angew Chem Int Ed Engl 2023; 62:e202216819. [PMID: 36585932 DOI: 10.1002/anie.202216819] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 01/01/2023]
Abstract
The convergence of supramolecular chemistry and single-molecule electronics offers a new perspective on supramolecular electronics, and provides a new avenue toward understanding and application of intermolecular charge transport at the molecular level. In this review, we will provide an overview of the advances in the characterization technique for the investigation of intermolecular charge transport, and summarize the experimental investigation of several non-covalent interactions, including π-π stacking interactions, hydrogen bonding, host-guest interactions and σ-σ interactions at the single-molecule level. We will also provide a perspective on supramolecular electronics and discuss the potential applications and future challenges.
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Affiliation(s)
- Xiaohui Li
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & College of Materials & IKKEM, Xiamen University, Xiamen, 361005, China
| | - Wenhui Ge
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & College of Materials & IKKEM, Xiamen University, Xiamen, 361005, China
| | - Shuhan Guo
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & College of Materials & IKKEM, Xiamen University, Xiamen, 361005, China
| | - Jie Bai
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & College of Materials & IKKEM, Xiamen University, Xiamen, 361005, China
| | - Wenjing Hong
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering & College of Materials & IKKEM, Xiamen University, Xiamen, 361005, China
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11
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Trasobares J, Martín-Romano JC, Khaliq MW, Ruiz-Gómez S, Foerster M, Niño MÁ, Pedraz P, Dappe YJ, de Ory MC, García-Pérez J, Acebrón M, Osorio MR, Magaz MT, Gomez A, Miranda R, Granados D. Hybrid molecular graphene transistor as an operando and optoelectronic platform. Nat Commun 2023; 14:1381. [PMID: 36914623 PMCID: PMC10011542 DOI: 10.1038/s41467-023-36714-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 02/13/2023] [Indexed: 03/16/2023] Open
Abstract
Lack of reproducibility hampers molecular devices integration into large-scale circuits. Thus, incorporating operando characterization can facilitate the understanding of multiple features producing disparities in different devices. In this work, we report the realization of hybrid molecular graphene field effect transistors (m-GFETs) based on 11-(Ferrocenyl)undecanethiol (FcC11SH) micro self-assembled monolayers (μSAMs) and high-quality graphene (Gr) in a back-gated configuration. On the one hand, Gr enables redox electron transfer, avoids molecular degradation and permits operando spectroscopy. On the other hand, molecular electrode decoration shifts the Gr Dirac point (VDP) to neutrality and generates a photocurrent in the Gr electron conduction regime. Benefitting from this heterogeneous response, the m-GFETs can implement optoelectronic AND/OR logic functions. Our approach represents a step forward in the field of molecular scale electronics with implications in sensing and computing based on sustainable chemicals.
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Affiliation(s)
- Jorge Trasobares
- IMDEA-Nanociencia, Cantoblanco, Madrid, 28049, Spain. .,Department of Biodiversity, Ecology and Evolution (Biomathematics), Universidad Complutense de Madrid, Madrid, 28040, Spain.
| | | | - Muhammad Waqas Khaliq
- ALBA Synchrotron, Carrer de la llum 2-26, Cerdanyola del Valles, 08290, Spain.,Department of Condensed Matter Physics, University of Barcelona, Barcelona, Spain
| | - Sandra Ruiz-Gómez
- ALBA Synchrotron, Carrer de la llum 2-26, Cerdanyola del Valles, 08290, Spain
| | - Michael Foerster
- ALBA Synchrotron, Carrer de la llum 2-26, Cerdanyola del Valles, 08290, Spain
| | - Miguel Ángel Niño
- ALBA Synchrotron, Carrer de la llum 2-26, Cerdanyola del Valles, 08290, Spain
| | | | - Yannick J Dappe
- Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, 28850, Spain
| | | | | | - María Acebrón
- IMDEA-Nanociencia, Cantoblanco, Madrid, 28049, Spain
| | | | | | - Alicia Gomez
- Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, 28850, Spain
| | - Rodolfo Miranda
- SPEC, CEA, CNRS Université Paris-Saclay, Gif-sur-Yvette, 91191, France.,Dpto. de Física de la Materia Condensada, Universidad Autónoma de Madrid, Cantoblanco, Spain
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12
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Gupta R, Fereiro JA, Bayat A, Pritam A, Zharnikov M, Mondal PC. Nanoscale molecular rectifiers. Nat Rev Chem 2023; 7:106-122. [PMID: 37117915 DOI: 10.1038/s41570-022-00457-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2022] [Indexed: 01/15/2023]
Abstract
The use of molecules bridged between two electrodes as a stable rectifier is an important goal in molecular electronics. Until recently, however, and despite extensive experimental and theoretical work, many aspects of our fundamental understanding and practical challenges have remained unresolved and prevented the realization of such devices. Recent advances in custom-designed molecular systems with rectification ratios exceeding 105 have now made these systems potentially competitive with existing silicon-based devices. Here, we provide an overview and critical analysis of recent progress in molecular rectification within single molecules, self-assembled monolayers, molecular multilayers, heterostructures, and metal-organic frameworks and coordination polymers. Examples of conceptually important and best-performing systems are discussed, alongside their rectification mechanisms. We present an outlook for the field, as well as prospects for the commercialization of molecular rectifiers.
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13
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Nguyen QV, Martin P, Lacroix JC. Probing the Effect of the Density of Active Molecules in Large-Area Molecular Junctions. J Phys Chem Lett 2022; 13:11990-11995. [PMID: 36537879 DOI: 10.1021/acs.jpclett.2c03027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The effect of the density of active molecules in molecular junctions (MJs) has been investigated by using a host/guest strategy. Mixed layers consisting of oligothiophene (BTB) encapsulated by β-cyclodextrin (BTB@β-CD) were generated. Cyclodextrins were then removed, and the pinholes generated were filled with BTB to obtain BTB@BTB films. MJs based on mixed BTB@β-CD and BTB@BTB layers, as well as single-component BTB MJs, were compared. The variation of ln J vs thickness is similar for all systems while the Jo of BTB@β-CD MJs is 20 times lower than that of BTB MJs. After β-cyclodextrin has been removed, and the pinholes filled, Jo increases and reaches the same value as for the BTB MJs, showing that the conductance scales with the number of active molecules. This strategy provides a unique method for investigating molecular interactions in direct tunneling MJs as well as the possibility of fabricating new functionalized MJs based on mixed layers.
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Affiliation(s)
- Quyen Van Nguyen
- Université Paris Cité, ITODYS, CNRS UMR 7086, 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, 11307 Cau Giay, Hanoi Vietnam
| | - Pascal Martin
- Université Paris Cité, ITODYS, CNRS UMR 7086, 15 rue Jean-Antoine de Baïf, 75205 Paris Cedex 13, France
| | - Jean Christophe Lacroix
- Université Paris Cité, ITODYS, CNRS UMR 7086, 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, 11307 Cau Giay, Hanoi Vietnam
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14
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Wang Z, Palma JL, Wang H, Liu J, Zhou G, Ajayakumar MR, Feng X, Wang W, Ulstrup J, Kornyshev AA, Li Y, Tao N. Electrochemically controlled rectification in symmetric single-molecule junctions. Proc Natl Acad Sci U S A 2022; 119:e2122183119. [PMID: 36136968 PMCID: PMC9522371 DOI: 10.1073/pnas.2122183119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Single-molecule electrochemical science has advanced over the past decades and now extends well beyond molecular imaging, to molecular electronics functions such as rectification and amplification. Rectification is conceptually the simplest but has involved mostly challenging chemical synthesis of asymmetric molecular structures or asymmetric materials and geometry of the two enclosing electrodes. Here we propose an experimental and theoretical strategy for building and tuning in situ (in operando) rectification in two symmetric molecular structures in electrochemical environment. The molecules were designed to conduct electronically via either their lowest unoccupied molecular orbital (LUMO; electron transfer) or highest occupied molecular orbital (HOMO; "hole transfer"). We used a bipotentiostat to control separately the electrochemical potential of the tip and substrate electrodes of an electrochemical scanning tunneling microscope (EC-STM), which leads to independent energy alignment of the STM tip, the molecule, and the STM substrate. By creating an asymmetric energy alignment, we observed single-molecule rectification of each molecule within a voltage range of ±0.5 V. By varying both the dominating charge transporting LUMO or HOMO energy and the electrolyte concentration, we achieved tuning of the polarity as well as the amplitude of the rectification. We have extended an earlier proposed theory that predicts electrolyte-controlled rectification to rationalize all the observed in situ rectification features and found excellent agreement between theory and experiments. Our study thus offers a way toward building controllable single-molecule rectifying devices without involving asymmetric molecular structures.
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Affiliation(s)
- Zixiao Wang
- aState Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
- 1To whom correspondence may be addressed. or or or
| | - Julio L. Palma
- bDepartment of Chemistry, Pennsylvania State University, Fayette, The Eberly Campus, Lemont Furnace, PA 15456
| | - Hui Wang
- aState Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Junzhi Liu
- cDepartment of Chemistry and State Key Laboratory of Synthetic Chemistry, the University of Hong Kong, Hong Kong, China
| | - Gang Zhou
- dLaboratory of Advanced Materials, State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai 200438, China
| | - M. R. Ajayakumar
- eCentre for Advancing Electronics Dresden, Faculty of Chemistry and Food Chemistry, Technische University Dresden, 01062 Dresden, Germany
| | - Xinliang Feng
- eCentre for Advancing Electronics Dresden, Faculty of Chemistry and Food Chemistry, Technische University Dresden, 01062 Dresden, Germany
| | - Wei Wang
- aState Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Jens Ulstrup
- fDepartment of Chemistry, Technical University of Denmark, Kongens Lyngby 2800, Denmark
- 1To whom correspondence may be addressed. or or or
| | - Alexei A. Kornyshev
- gDepartment of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, London W12 0BZ, United Kingdom
- 1To whom correspondence may be addressed. or or or
| | - Yueqi Li
- hCenter for Bioanalytical Chemistry, University of Science and Technology of China, Hefei 230026, China
- 1To whom correspondence may be addressed. or or or
| | - Nongjian Tao
- aState Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
- iCenter for Bioelectronics and Biosensors, Biodesign Institute and School of Electrical, Energy and Computer Engineering, Arizona State University, Tempe, AZ 85287
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15
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Li S, Coffinier Y, Lagadec C, Cleri F, Nishiguchi K, Fujiwara A, Fujii T, Kim SH, Clément N. Redox-labelled electrochemical aptasensors with nanosupported cancer cells. Biosens Bioelectron 2022; 216:114643. [PMID: 36030742 DOI: 10.1016/j.bios.2022.114643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 07/31/2022] [Accepted: 08/16/2022] [Indexed: 11/30/2022]
Abstract
The transfer of redox-labelled bioelectrochemical sensors from proteins to cells is not straightforward because of the cell downward force issue on the surface of the sensors. In this paper, 20-nm-thick nanopillars are introduced to overcome this issue, in a well-controlled manner. We show on both molecular dynamics simulations and experiments that suspending cells a few nanometers above an electrode surface enables redox-labelled tethered DNA aptamer probes to move freely, while remaining at an interaction distance from a target membrane protein, i. e. epithelial cell adhesion molecule (EpCAM), which is typically overexpressed in cancer cells. By this nanopillar configuration, the interaction of aptamer with cancer cells is clearly observable, with 13 cells as the lower limit of detection. Nanoconfinement induced by the gap between the electrode surface and the cell membrane appears to improve the limit of detection and to lower the melting temperature of DNA aptamer hairpins, offering an additional degree of freedom to optimize molecular recognition mechanisms. This novel nanosupported electrochemical DNA cell sensor scheme including Brownian-fluctuating redox species opens new opportunities for the design of all-electrical sensors using redox-labelled probes.
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Affiliation(s)
- S Li
- IIS, LIMMS/CNRS-IIS IRL2820, The Univ. of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo, 153-8505, Japan.
| | - Y Coffinier
- IEMN, CNRS UMR8520, Univ. Lille Avenue Poincaré, BP 60069, Villeneuve D'Ascq Cedex, 59652, France
| | - C Lagadec
- Univ. Lille, CNRS, Inserm, CHU Lille, Centre Oscar Lambret, UMR9020 - UMR-S 1277 - Canther - Cancer Heterogeneity, Plasticity and Resistance to Therapies, F-59000, Lille, France
| | - F Cleri
- IEMN, CNRS UMR8520, Univ. Lille Avenue Poincaré, BP 60069, Villeneuve D'Ascq Cedex, 59652, France
| | - K Nishiguchi
- NTT Basic Research Laboratories, NTT Corporation, 3-1, Morinosato-Wakamiya, Atsugi-shi, 243-0198, Japan
| | - A Fujiwara
- NTT Basic Research Laboratories, NTT Corporation, 3-1, Morinosato-Wakamiya, Atsugi-shi, 243-0198, Japan
| | - T Fujii
- IIS, LIMMS/CNRS-IIS IRL2820, The Univ. of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo, 153-8505, Japan
| | - S-H Kim
- IIS, LIMMS/CNRS-IIS IRL2820, The Univ. of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo, 153-8505, Japan
| | - N Clément
- IIS, LIMMS/CNRS-IIS IRL2820, The Univ. of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo, 153-8505, Japan.
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16
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Han Y, Jiang L, Meany JE, Wang Y, Woski SA, Johnson MS, Nijhuis CA, Metzger RM. Verification and Temperature-Dependent Rectification by HBQ, the Smallest Unimolecular Donor-Acceptor Rectifier. ACS OMEGA 2022; 7:28790-28796. [PMID: 36033727 PMCID: PMC9404471 DOI: 10.1021/acsomega.2c01182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 06/30/2022] [Indexed: 06/15/2023]
Abstract
Five years ago, rectification of electrical current was found in 4'-bromo-3,4-dicyano-2',5'-dimethoxy-[1,1'-biphenyl]-2,5-dione (1), a hemibiquinone (which we will call either 1 or HBQ) that has a very small working length (1.1 nm). Monolayers of HBQ on AuTS were detected by "nanodozing" atomic force microscopy (AFM) and were contacted with two types of top electrodes: either cold Au or eutectic Ga-In. Here, we describe cyclic voltammetry of a self-assembled monolayer (SAM) of HBQ and its orientation on a gold substrate with angle-resolved X-ray photoelectron spectroscopy. New measurements of its rectification as a monolayer as a function of bias range and temperature confirm and prove that HBQ is truly the smallest donor-acceptor rectifier and provide some insight into the mechanism of rectification.
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Affiliation(s)
- Yingmei Han
- Department
of Chemistry, and Centre for Advanced 2D Materials, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Li Jiang
- Department
of Chemistry, and Centre for Advanced 2D Materials, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Joseph E. Meany
- Department
of Chemistry and Biochemistry, University
of Alabama, Tuscaloosa, Alabama 35487-0336, United States
- Savannah
River National Laboratory, Aiken, South Carolina 29808, United States
| | - Yulong Wang
- Department
of Chemistry, and Centre for Advanced 2D Materials, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Stephen A. Woski
- Department
of Chemistry and Biochemistry, University
of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | - Marcus S. Johnson
- Department
of Chemistry and Biochemistry, University
of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | - Christian A. Nijhuis
- Department
of Chemistry, and Centre for Advanced 2D Materials, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
- Hybrid
Materials for Opto-Electronics Group, 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
| | - Robert M. Metzger
- Department
of Chemistry and Biochemistry, University
of Alabama, Tuscaloosa, Alabama 35487-0336, United States
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17
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Li P, Zhou L, Zhao C, Ju H, Gao Q, Si W, Cheng L, Hao J, Li M, Chen Y, Jia C, Guo X. Single-molecule nano-optoelectronics: insights from physics. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2022; 85:086401. [PMID: 35623319 DOI: 10.1088/1361-6633/ac7401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
Single-molecule optoelectronic devices promise a potential solution for miniaturization and functionalization of silicon-based microelectronic circuits in the future. For decades of its fast development, this field has made significant progress in the synthesis of optoelectronic materials, the fabrication of single-molecule devices and the realization of optoelectronic functions. On the other hand, single-molecule optoelectronic devices offer a reliable platform to investigate the intrinsic physical phenomena and regulation rules of matters at the single-molecule level. To further realize and regulate the optoelectronic functions toward practical applications, it is necessary to clarify the intrinsic physical mechanisms of single-molecule optoelectronic nanodevices. Here, we provide a timely review to survey the physical phenomena and laws involved in single-molecule optoelectronic materials and devices, including charge effects, spin effects, exciton effects, vibronic effects, structural and orbital effects. In particular, we will systematically summarize the basics of molecular optoelectronic materials, and the physical effects and manipulations of single-molecule optoelectronic nanodevices. In addition, fundamentals of single-molecule electronics, which are basic of single-molecule optoelectronics, can also be found in this review. At last, we tend to focus the discussion on the opportunities and challenges arising in the field of single-molecule optoelectronics, and propose further potential breakthroughs.
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Affiliation(s)
- Peihui Li
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
| | - Li Zhou
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
| | - Cong Zhao
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
| | - Hongyu Ju
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, People's Republic of China
| | - Qinghua Gao
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
| | - Wei Si
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
| | - Li Cheng
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
| | - Jie Hao
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
| | - Mengmeng Li
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
| | - Yijian Chen
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
| | - Chuancheng Jia
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
- Beijing National Laboratory for Molecular Sciences, National Biomedical Imaging Center, College of Chemistry and Molecular Engineering, Peking University, 292 Chengfu Road, Haidian District, Beijing 100871, People's Republic of China
| | - Xuefeng Guo
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, Tianjin Key Laboratory of Micro-Scale Optical Information Science and Technology, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, People's Republic of China
- Beijing National Laboratory for Molecular Sciences, National Biomedical Imaging Center, College of Chemistry and Molecular Engineering, Peking University, 292 Chengfu Road, Haidian District, Beijing 100871, People's Republic of China
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18
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Dynamics of Spin Crossover Molecular Complexes. NANOMATERIALS 2022; 12:nano12101742. [PMID: 35630963 PMCID: PMC9144206 DOI: 10.3390/nano12101742] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/09/2022] [Accepted: 05/16/2022] [Indexed: 02/04/2023]
Abstract
We review the current understanding of the time scale and mechanisms associated with the change in spin state in transition metal-based spin crossover (SCO) molecular complexes. Most time resolved experiments, performed by optical techniques, rely on the intrinsic light-induced switching properties of this class of materials. The optically driven spin state transition can be mediated by a rich interplay of complexities including intermediate states in the spin state transition process, as well as intermolecular interactions, temperature, and strain. We emphasize here that the size reduction down to the nanoscale is essential for designing SCO systems that switch quickly as well as possibly retaining the memory of the light-driven state. We argue that SCO nano-sized systems are the key to device applications where the “write” speed is an important criterion.
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19
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Qiu X, Chiechi RC. Printable logic circuits comprising self-assembled protein complexes. Nat Commun 2022; 13:2312. [PMID: 35484124 PMCID: PMC9050843 DOI: 10.1038/s41467-022-30038-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 04/08/2022] [Indexed: 11/09/2022] Open
Abstract
This paper describes the fabrication of digital logic circuits comprising resistors and diodes made from protein complexes and wired together using printed liquid metal electrodes. These resistors and diodes exhibit temperature-independent charge-transport over a distance of approximately 10 nm and require no encapsulation or special handling. The function of the protein complexes is determined entirely by self-assembly. When induced to self-assembly into anisotropic monolayers, the collective action of the aligned dipole moments increases the electrical conductivity of the ensemble in one direction and decreases it in the other. When induced to self-assemble into isotropic monolayers, the dipole moments are randomized and the electrical conductivity is approximately equal in both directions. We demonstrate the robustness and utility of these all-protein logic circuits by constructing pulse modulators based on AND and OR logic gates that function nearly identically to simulated circuits. These results show that digital circuits with useful functionality can be derived from readily obtainable biomolecules using simple, straightforward fabrication techniques that exploit molecular self-assembly, realizing one of the primary goals of molecular electronics. Proteins are promising molecular materials for next-generation electronic devices. Here, the authors fabricated printable digital logic circuits comprising resistors and diodes from self-assembled photosystem I complexes that enable pulse modulation.
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Affiliation(s)
- Xinkai Qiu
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands. .,Optoelectronics Group, Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK.
| | - Ryan C Chiechi
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands. .,Department of Chemistry, North Carolina State University, Raleigh, NC, 27695-8204, United States.
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20
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Bâldea I. Are Asymmetric SAM‐Induced Work Function Modifications Relevant for Real Molecular Rectifiers? ADVANCED THEORY AND SIMULATIONS 2022. [DOI: 10.1002/adts.202200077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ioan Bâldea
- Theoretical Chemistry Heidelberg University Im Neuenheimer Feld 229 Heidelberg D‐69120 Germany
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21
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Ganguly S, Maiti SK. Efficient current rectification in driven acenes. Phys Chem Chem Phys 2022; 24:28436-28443. [DOI: 10.1039/d2cp03823d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We examine the current–voltage (I–V) characteristics of different polyacenes, such as anthracene, tetracene, pentacene, etc., under the influence of an arbitrarily polarized light.
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Affiliation(s)
- Sudin Ganguly
- Department of Physics, School of Applied Sciences, University of Science and Technology Meghalaya, Ri-Bhoi-793 101, India
| | - Santanu K. Maiti
- Physics and Applied Mathematics Unit, Indian Statistical Institute, 203 Barrackpore Trunk Road, Kolkata-700 108, India
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22
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Grall S, Alić I, Pavoni E, Awadein M, Fujii T, Müllegger S, Farina M, Clément N, Gramse G. Attoampere Nanoelectrochemistry. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2101253. [PMID: 34121314 DOI: 10.1002/smll.202101253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 04/19/2021] [Indexed: 06/12/2023]
Abstract
Electrochemical microscopy techniques have extended the understanding of surface chemistry to the micrometer and even sub-micrometer level. However, fundamental questions related to charge transport at the solid-electrolyte interface, such as catalytic reactions or operation of individual ion channels, require improved spatial resolutions down to the nanoscale. A prerequisite for single-molecule electrochemical sensitivity is the reliable detection of a few electrons per second, that is, currents in the atto-Ampere (10-18 A) range, 1000 times below today's electrochemical microscopes. This work reports local cyclic voltammetry (CV) measurements at the solid-liquid interface on ferrocene self-assembled monolayer (SAM) with sub-atto-Ampere sensitivity and simultaneous spatial resolution < 80 nm. Such sensitivity is obtained through measurements of the charging of the local faradaic interface capacitance at GHz frequencies. Nanometer-scale details of different molecular organizations with a 19% packing density difference are resolved, with an extremely small dispersion of the molecular electrical properties. This is predicted previously based on weak electrostatic interactions between neighboring redox molecules in a SAM configuration. These results open new perspectives for nano-electrochemistry like the study of quantum mechanical resonance in complex molecules and a wide range of applications from electrochemical catalysis to biophysics.
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Affiliation(s)
- Simon Grall
- Institute of Biophysics, Johannes Kepler University, Linz, 4020, Austria
| | - Ivan Alić
- Institute of Biophysics, Johannes Kepler University, Linz, 4020, Austria
| | - Eleonora Pavoni
- Department of Information Engineering, Marche Polytechnic University, Ancona, 60131, Italy
| | - Mohamed Awadein
- Keysight Labs Austria, Keysight Technologies, Linz, 4020, Austria
| | - Teruo Fujii
- LIMMS/CNRS, Institute of Industrial Science, University of Tokyo, Tokyo, 153-8505, Japan
| | - Stefan Müllegger
- Institute of Semiconductor and Solid-State Physics, Johannes Kepler University, Linz, 4040, Austria
| | - Marco Farina
- Department of Information Engineering, Marche Polytechnic University, Ancona, 60131, Italy
| | - Nicolas Clément
- LIMMS/CNRS, Institute of Industrial Science, University of Tokyo, Tokyo, 153-8505, Japan
| | - Georg Gramse
- Institute of Biophysics, Johannes Kepler University, Linz, 4020, Austria
- Keysight Labs Austria, Keysight Technologies, Linz, 4020, Austria
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23
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Zhang XH, Liu SJ, Tian L, Wan Q, Hu AM, Li XF. Rectification with controllable directions in sulfur-doped armchair graphene nanoribbon heterojunctions. Chem Phys 2021. [DOI: 10.1016/j.chemphys.2021.111140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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24
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High-frequency rectifiers based on type-II Dirac fermions. Nat Commun 2021; 12:1584. [PMID: 33707448 PMCID: PMC7952558 DOI: 10.1038/s41467-021-21906-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 02/18/2021] [Indexed: 11/21/2022] Open
Abstract
The advent of topological semimetals enables the exploitation of symmetry-protected topological phenomena and quantized transport. Here, we present homogeneous rectifiers, converting high-frequency electromagnetic energy into direct current, based on low-energy Dirac fermions of topological semimetal-NiTe2, with state-of-the-art efficiency already in the first implementation. Explicitly, these devices display room-temperature photosensitivity as high as 251 mA W−1 at 0.3 THz in an unbiased mode, with a photocurrent anisotropy ratio of 22, originating from the interplay between the spin-polarized surface and bulk states. Device performances in terms of broadband operation, high dynamic range, as well as their high sensitivity, validate the immense potential and unique advantages associated to the control of nonequilibrium gapless topological states via built-in electric field, electromagnetic polarization and symmetry breaking in topological semimetals. These findings pave the way for the exploitation of topological phase of matter for high-frequency operations in polarization-sensitive sensing, communications and imaging. High-frequency rectifiers at terahertz regime are pivotal components in modern communication, whereas the drawbacks in semiconductor junctions-based devices inhibit their usages. Here, the authors report electromagnetic rectification with high signal-to-noise ratio driven by chiral Bloch-electrons in type-II Dirac semimetal NiTe2-based device allowing for efficient THz detection.
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Qiu X, Rousseva S, Ye G, Hummelen JC, Chiechi RC. In Operando Modulation of Rectification in Molecular Tunneling Junctions Comprising Reconfigurable Molecular Self-Assemblies. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2006109. [PMID: 33326147 DOI: 10.1002/adma.202006109] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 10/27/2020] [Indexed: 06/12/2023]
Abstract
The reconfiguration of molecular tunneling junctions during operation via the self-assembly of bilayers of glycol ethers is described. Well-established functional groups are used to modulate the magnitude and direction of rectification in assembled tunneling junctions by exposing them to solutions containing different glycol ethers. Variable-temperature measurements confirm that rectification occurs by the expected bias-dependent tunneling-hopping mechanism for these functional groups and that glycol ethers, besides being an unusually efficient tunneling medium, behave similarly to alkanes. Memory bits are fabricated from crossbar junctions prepared by injecting eutectic Ga-In (EGaIn) into microfluidic channels. The states of two 8-bit registers were set by trains of droplets such that they are able to perform logical AND operations on bit strings encoded into chemical packets that alter the composition of the crossbar junctions through self-assembly to effect memristor-like properties. This proof-of-concept work demonstrates the potential for fieldable devices based on molecular tunneling junctions comprising self-assembled monolayers and bilayers.
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Affiliation(s)
- Xinkai Qiu
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands
| | - Sylvia Rousseva
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands
| | - Gang Ye
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands
| | - Jan C Hummelen
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands
| | - Ryan C Chiechi
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, Netherlands
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Karthäuser S, Peter S, Simon U. Integration of Individual Functionalized Gold Nanoparticles into Nanoelectrode Configurations: Recent Advances. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000629] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Silvia Karthäuser
- Peter Grünberg Institut (PGI‐7) and JARA‐FIT Forschungszentrum Jülich GmbH 52425 Jülich Germany
| | - Sophia Peter
- Institute of Inorganic Chemistry and JARA‐FIT RWTH Aachen University 52074 Aachen Germany
| | - Ulrich Simon
- Institute of Inorganic Chemistry and JARA‐FIT RWTH Aachen University 52074 Aachen Germany
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27
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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: 71] [Impact Index Per Article: 17.8] [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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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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29
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Krzykawska A, Wróbel M, Kozieł K, Cyganik P. N-Heterocyclic Carbenes for the Self-Assembly of Thin and Highly Insulating Monolayers with High Quality and Stability. ACS NANO 2020; 14:6043-6057. [PMID: 32343123 DOI: 10.1021/acsnano.0c01733] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
As an organic nanostructure, self-assembled monolayers (SAMs) play a central role in many aspects of nanotechnology, including molecular electronics. In this work, we show that SAMs based on N-heterocyclic carbenes on a Au(111) substrate offer a high level of crystallinity and also exhibit the highest possible packing density. As a result of this structural optimization, defect concentrations were reduced by 2-3 orders of magnitude and thermal stability was ∼100 K higher than those of any other SAMs on Au. The conductivity of these SAMs is ∼4 orders of magnitude lower than that of standard alkanethiols of comparable length, which together with very low defect concentration and high thermal stability makes them a highly interesting material for potential application in organic thin film transistors. The self-assembly of such dense, highly crystalline, and notably stable structures is associated with strong C-Au bonding and the rational design of assembled molecules, resulting in the high mobility of both adsorbate and substrate atoms, as confirmed by the size of the molecular domains and the adsorbate-driven modification of the Au(111) substrate, respectively.
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Affiliation(s)
- Anna Krzykawska
- Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza 11, 30-348 Krakow, Poland
| | - Mateusz Wróbel
- Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza 11, 30-348 Krakow, Poland
| | - Krzysztof Kozieł
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Krakow, Poland
| | - Piotr Cyganik
- Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza 11, 30-348 Krakow, Poland
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30
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Sergi Lopes C, Merces L, de Oliveira RF, de Camargo DHS, Bof Bufon CC. Rectification ratio and direction controlled by temperature in copper phthalocyanine ensemble molecular diodes. NANOSCALE 2020; 12:10001-10009. [PMID: 32196026 DOI: 10.1039/c9nr10601d] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Organic diodes and molecular rectifiers are fundamental electronic devices that share one common feature: current rectification ability. Since both present distinct spatial dimensions and working principles, the rectification of organic diodes is usually achieved by interface engineering, while changes in molecular structures commonly control the molecular rectifiers' features. Here, we report on the first observation of temperature-driven inversion of the rectification direction (IRD) in ensemble molecular diodes (EMDs) prepared in a vertical stack configuration. The EMDs are composed of 20 nm thick molecular ensembles of copper phthalocyanine in close contact with one of its fluorinated derivatives. The material interface was found to be responsible for modifying the junction's conduction mechanisms from nearly activationless transport to Poole-Frenkel emission and phonon-assisted tunneling. In this context, the current rectification was found to be dependent on the interplay of such distinct charge transport mechanisms. The temperature has played a crucial role in each charge transport transition, which we have investigated via electrical measurements and band diagram analysis, thus providing the fundamentals on the IRD occurrence. Our findings represent an important step towards simple and rational control of rectification in carbon-based electronic nanodevices.
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Affiliation(s)
- Carolina Sergi Lopes
- Brazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), 13083-970, Campinas, São Paulo, Brazil
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31
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Liu Y, Zhong M, Downey EF, Chen X, Li T, Nørgaard K, Wei Z. Temperature dependence of charge transport in solid-state molecular junctions based on oligo(phenylene ethynylene)s. NANOTECHNOLOGY 2020; 31:164001. [PMID: 31891933 DOI: 10.1088/1361-6528/ab6681] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The ultimate goal of molecular electronics is to achieve practical applications. For approaching the target, we have successfully fabricated solid-state junctions based on oligo(phenylene ethynylene)s (OPEs) and cruciform OPEs with extended tetrathiafulvalene (TTF) (OPE3 and OPE3-TTF) self-assembled monolayers (SAMs) with a diamine anchoring group. SAMs were confined in micropores with gold substrates to ensure well-defined device surface areas. The transport properties were conducted on a double-junction layout, which the rGO films used for top contacts and interconnects between adjacent SAMs. The solid-state devices based on OPE3-TTF SAMs showed the expected higher conductance under ambient conditions because of the incorporation of a TTF moiety. The two devices displayed varying degrees of temperature dependence with decreasing temperature, which resulted from the cross-conjugated OPE3-TTF molecule exhibiting quantum interference while the linear-conjugated OPE3 molecule did not. This study shows the temperature dependence of the electrical properties of molecular devices based on cruciform OPEs, further enriching the research results of functional molecular devices.
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Affiliation(s)
- Yuqing Liu
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences & Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100083, People's Republic of China. Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China. Nano-Science Center and Department of Chemistry, University of Copenhagen, Copenhagen DK-2100, Denmark
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32
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Walkey MC, Peiris CR, Ciampi S, C Aragonès A, Domínguez-Espíndola RB, Jago D, Pulbrook T, Skelton BW, Sobolev AN, Díez Pérez I, Piggott MJ, Koutsantonis GA, Darwish N. Chemically and Mechanically Controlled Single-Molecule Switches Using Spiropyrans. ACS APPLIED MATERIALS & INTERFACES 2019; 11:36886-36894. [PMID: 31522492 DOI: 10.1021/acsami.9b11044] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Developing molecular circuits that can function as the active components in electrical devices is an ongoing challenge in molecular electronics. It demands mechanical stability of the single-molecule circuit while simultaneously being responsive to external stimuli mimicking the operation of conventional electronic components. Here, we report single-molecule circuits based on spiropyran derivatives that respond electrically to chemical and mechanical stimuli. The merocyanine that results from the protonation/ring-opening of the spiropyran form showed single-molecule diode characteristics, with an average current rectification ratio of 5 at ±1 V, favoring the orientation where the positively charged end of the molecule is attached to the negative terminal of the circuit. Mechanical pulling of a single spiropyran molecule drives a switch to a more conducting merocyanine state. The mechanical switching is enabled by the strong Au-C covalent bonding between the molecule and the electrodes, which allows the tensile force delivered by the STM piezo to break the molecule at its spiropyran C-O bond.
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Affiliation(s)
| | - Chandramalika R Peiris
- School of Molecular Science and Curtin Institute of Functional Molecules and Interfaces , Curtin University , Bentley , WA 6102 , Australia
| | - Simone Ciampi
- School of Molecular Science and Curtin Institute of Functional Molecules and Interfaces , Curtin University , Bentley , WA 6102 , Australia
| | - Albert C Aragonès
- Department of Chemistry, Faculty of Natural & Mathematical Sciences , King's College London , Britannia House, 7 Trinity Street , London SE1 1DB , United Kingdom
| | - Ruth B Domínguez-Espíndola
- School of Molecular Science and Curtin Institute of Functional Molecules and Interfaces , Curtin University , Bentley , WA 6102 , Australia
| | | | | | | | | | - Ismael Díez Pérez
- Department of Chemistry, Faculty of Natural & Mathematical Sciences , King's College London , Britannia House, 7 Trinity Street , London SE1 1DB , United Kingdom
| | | | | | - Nadim Darwish
- School of Molecular Science and Curtin Institute of Functional Molecules and Interfaces , Curtin University , Bentley , WA 6102 , Australia
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Pohl V, Marsoner Steinkasserer LE, Tremblay JC. Imaging Time-Dependent Electronic Currents through a Graphene-Based Nanojunction. J Phys Chem Lett 2019; 10:5387-5394. [PMID: 31448920 DOI: 10.1021/acs.jpclett.9b01732] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
To assist the design of efficient molecular junctions, a precise understanding of the charge transport mechanisms through nanoscaled devices is of prime importance. In the present contribution, we present time- and space-resolved electron transport simulations through a nanojunction under time-dependent potential biases. We use the driven Liouville-von Neumann approach to simulate the time evolution of the one-electron density matrix under nonequilibrium conditions, which allows us to capture the ultrafast scattering dynamics, the electronic relaxation process, and the quasi-stationary current limit from the same simulation. Using local projection techniques, we map the coherent electronic current density, unraveling insightful mechanistic details of the transport on time scales ranging from atto- to picoseconds. Memory effects dominate the early time transport process, and they reveal different current patterns on short time scales in comparison to those in the long-time regime. For nanotransistors with high switching rates, the scattering perspective on electron transport should thus be favored.
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Affiliation(s)
- Vincent Pohl
- Quantum on Demand , c/o Freie Universität Berlin , Altensteinstr. 40 , 14195 Berlin , Germany
- Institut für Chemie und Biochemie , Freie Universität Berlin , Takustr. 3 , 14195 Berlin , Germany
| | | | - Jean Christophe Tremblay
- Laboratoire de Physique et Chimie Théoriques , CNRS-Université de Lorraine , UMR 7019, ICPM, 1 Bd Arago , 57070 Metz , France
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35
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Rudge SL, Kosov DS. Counting quantum jumps: A summary and comparison of fixed-time and fluctuating-time statistics in electron transport. J Chem Phys 2019; 151:034107. [DOI: 10.1063/1.5108518] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Samuel L. Rudge
- College of Science and Engineering, James Cook University, Townsville, QLD, 4814, Australia
| | - Daniel S. Kosov
- College of Science and Engineering, James Cook University, Townsville, QLD, 4814, Australia
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36
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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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37
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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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38
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Zwolak M. Communication: Gibbs phenomenon and the emergence of the steady-state in quantum transport. J Chem Phys 2018; 149:241102. [PMID: 30599719 PMCID: PMC6602063 DOI: 10.1063/1.5061759] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Simulations are increasingly employing explicit reservoirs-internal, finite regions-to drive electronic or particle transport. This naturally occurs in simulations of transport via ultracold atomic gases. Whether the simulation is numerical or physical, these approaches rely on the rapid development of the steady state. We demonstrate that steady state formation is a manifestation of the Gibbs phenomenon well-known in signal processing and in truncated discrete Fourier expansions. Each particle separately develops into an individual steady state due to the spreading of its wave packet in energy. The rise to the steady state for an individual particle depends on the particle energy-and thus can be slow-and ringing oscillations appear due to filtering of the response through the electronic bandwidth. However, the rise to the total steady state-the one from all particles-is rapid, with time scale π/W, where W is the bandwidth. Ringing oscillations are now also filtered through the bias window, and they decay with a higher power. The Gibbs constant-the overshoot of the first ring-can appear in the simulation error. These results shed light on the formation of the steady state and support the practical use of explicit reservoirs to simulate transport at the nanoscale or using ultracold atomic lattices.
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Affiliation(s)
- Michael Zwolak
- Biophysics Group, Microsystems and Nanotechnology Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
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39
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Eklöf-Österberg J, Gschneidtner T, Tebikachew B, Lara-Avila S, Moth-Poulsen K. Parallel Fabrication of Self-Assembled Nanogaps for Molecular Electronic Devices. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1803471. [PMID: 30358919 DOI: 10.1002/smll.201803471] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 10/04/2018] [Indexed: 06/08/2023]
Abstract
Single molecule electronics might be a way to add additional function to nanoscale devices and continue miniaturization beyond current state of the art. Here, a combined top-down and bottom-up strategy is employed to assemble single molecules onto prefabricated electrodes. Protodevices, which are self-assembled nanogaps composed by two gold nanoparticles linked by a single or a few molecules, are guided onto top-down prefabricated nanosized nickel electrodes with sandwiched palladium layers. It is shown that an optimized geometry of multilayered metallic (top-down) electrodes facilitates the assembly of (bottom-up) nanostructures by surface charge interactions. Moreover, such assembly process results in an electrode-nanoparticle interface free from linking molecules that enable electrical measurements to probe electron transport properties of the nanoparticle-molecule-nanoparticle protodevices.
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Affiliation(s)
- Johnas Eklöf-Österberg
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, 412 96, Sweden
| | - Tina Gschneidtner
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, 412 96, Sweden
| | - Behabitu Tebikachew
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, 412 96, Sweden
| | - Samuel Lara-Avila
- Department of Microtechnology and Nanoscience, Chalmers University of Technology, Gothenburg, 412 96, Sweden
- National Physical Laboratory, Teddington, TW11 0LW, UK
| | - Kasper Moth-Poulsen
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, 412 96, Sweden
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40
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Cheng N, Chen F, Durkan C, Wang N, He Y, Zhao J. Electron transport behavior of quinoidal heteroacene-based junctions: effective electron-transport pathways and quantum interference. Phys Chem Chem Phys 2018; 20:28860-28870. [PMID: 30420983 DOI: 10.1039/c8cp05901b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The electron transport behavior through a series of molecular junctions composed of tetracene (TC) and S/O substituted-TC (S/O-TC) has been studied using density functional theory (DFT) combined with the non-equilibrium Green's function (NEGF) method. The unique transport behavior has been interpreted using correlated quantum interference and electron transport pathway models. In the TC system, two dominant electron transfer channels exist as demonstrated by a detailed transmission pathway analysis. In the substituted S/O-TC systems, the electron transport behavior is regulated through either constructive or destructive quantum interference due to the existence of additional p-electrons, leading to a significant diversity of current-voltage curves. Compared to the TC molecule in the bias region from 0 to 1.0 V, an α-connected molecular junction exhibits a greater current, whereas a β-connected molecular junction shows a smaller current. The substitution with O and S atoms shows a minor effect on the conductance of the molecular junctions. In order to clarify the role of heteroatoms, a series of artificial models designed by removing specific sulfur and carbon atoms in α-S-TC have been investigated in detail. The results have demonstrated that only the S heteroatom on one side of the molecule contributes to the junction conductivity through constructive quantum interference. It has also been observed that current exchange occurs between the two electron transfer channels.
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Affiliation(s)
- Na Cheng
- College of Material and Textile Engineering, China-Australia Institute for Advanced Materials and Manufacturing, Jiaxing University, Jiaxing 314001, China.
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41
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Yamada R, Albrecht K, Ohto T, Minode K, Yamamoto K, Tada H. Single-molecule rectifiers based on voltage-dependent deformation of molecular orbitals in carbazole oligomers. NANOSCALE 2018; 10:19818-19824. [PMID: 30334558 DOI: 10.1039/c8nr06049e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Current-voltage characteristics of single molecule junctions are governed both by the energy level alignment of molecular orbitals with respect to the Fermi level of the electrodes and by the hybridization of electronic structures at the interface between the molecule and the electrodes. While there have been many studies on tuning the former, only a few works intended to control the latter. In the present study, we demonstrate that molecular junctions based on carbazole oligomers showed a current rectification behavior due to asymmetric-symmetric control of electronic hybridization between the molecule and electrodes at the both terminals. The carbazole oligomers originally showed an asymmetric molecular orbital and, hence, electronic hybridization with the electrodes because of the electric dipole moment. Symmetric electronic hybridization was achieved when the applied electric field between electrodes deformed molecular orbital to be symmetric. This is a novel way to control charge transport in single-molecule junctions.
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Affiliation(s)
- Ryo Yamada
- Graduate School of Engineering Science, Osaka Univ., Japan.
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42
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Elenewski JE, Gruss D, Zwolak M. Communication: Master equations for electron transport: The limits of the Markovian limit. J Chem Phys 2018; 147:151101. [PMID: 29055298 DOI: 10.1063/1.5000747] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Master equations are increasingly popular for the simulation of time-dependent electronic transport in nanoscale devices. Several recent Markovian approaches use "extended reservoirs"-explicit degrees of freedom associated with the electrodes-distinguishing them from many previous classes of master equations. Starting from a Lindblad equation, we develop a common foundation for these approaches. Due to the incorporation of explicit electrode states, these methods do not require a large bias or even "true Markovianity" of the reservoirs. Nonetheless, their predictions are only physically relevant when the Markovian relaxation is weaker than the thermal broadening and when the extended reservoirs are "sufficiently large," in a sense that we quantify. These considerations hold despite complete positivity and respect for Pauli exclusion at any relaxation strength.
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Affiliation(s)
- Justin E Elenewski
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Daniel Gruss
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Michael Zwolak
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
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43
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Abstract
This paper reviews the present status of unimolecular electronics (UME). The field started in the 1970s with a hope that some day organic molecules (∼2 nm in size), when used as electronic components, would challenge Si-based inorganic electronics in ultimate-high-density integrated circuits. The technological push to ever smaller inorganic device sizes (Moore's "law") was driven by a profit motive and by vast investments. UME, the underfunded pauper, may have lost that "race to the bottom", but some excellent science is left to be done.
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Affiliation(s)
- Robert Melville Metzger
- Laboratory for Molecular Electronics, Department of Chemistry and Biochemistry, University of Alabama, Box 870336, Tuscaloosa, AL 35487-0336, USA.
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44
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Song P, Guerin S, Tan SJR, Annadata HV, Yu X, Scully M, Han YM, Roemer M, Loh KP, Thompson D, Nijhuis CA. Stable Molecular Diodes Based on π-π Interactions of the Molecular Frontier Orbitals with Graphene Electrodes. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:1706322. [PMID: 29356141 DOI: 10.1002/adma.201706322] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 12/01/2017] [Indexed: 06/07/2023]
Abstract
In molecular electronics, it is important to control the strength of the molecule-electrode interaction to balance the trade-off between electronic coupling strength and broadening of the molecular frontier orbitals: too strong coupling results in severe broadening of the molecular orbitals while the molecular orbitals cannot follow the changes in the Fermi levels under applied bias when the coupling is too weak. Here, a platform based on graphene bottom electrodes to which molecules can bind via π-π interactions is reported. These interactions are strong enough to induce electronic function (rectification) while minimizing broadening of the molecular frontier orbitals. Molecular tunnel junctions are fabricated based on self-assembled monolayers (SAMs) of Fc(CH2 )11 X (Fc = ferrocenyl, X = NH2 , Br, or H) on graphene bottom electrodes contacted to eutectic alloy of gallium and indium top electrodes. The Fc units interact more strongly with graphene than the X units resulting in SAMs with the Fc at the bottom of the SAM. The molecular diodes perform well with rectification ratios of 30-40, and they are stable against bias stressing under ambient conditions. Thus, tunnel junctions based on graphene with π-π molecule-electrode coupling are promising platforms to fabricate stable and well-performing molecular diodes.
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Affiliation(s)
- Peng Song
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Sarah Guerin
- Department of Physics, Bernal Institute, University of Limerick, Limerick, V94 T9PX, Ireland
| | - Sherman Jun Rong Tan
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Harshini Venkata Annadata
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Xiaojiang Yu
- Singapore Synchrotron Light Source, National University of Singapore, 5 Research Link, Singapore, 117603, Singapore
| | - Micheál Scully
- Department of Physics, Bernal Institute, University of Limerick, Limerick, V94 T9PX, Ireland
| | - Ying Mei Han
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Max Roemer
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Kian Ping Loh
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
- Centre for Advanced 2D Materials, Graphene Research Centre, National University of Singapore, 6 Science Drive 2, Singapore, 117546, Singapore
| | - Damien Thompson
- Department of Physics, Bernal Institute, University of Limerick, Limerick, V94 T9PX, Ireland
| | - Christian A Nijhuis
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
- Centre for Advanced 2D Materials, 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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45
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Morteza Najarian A, Bayat A, McCreery RL. Orbital Control of Photocurrents in Large Area All-Carbon Molecular Junctions. J Am Chem Soc 2018; 140:1900-1909. [DOI: 10.1021/jacs.7b12577] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Amin Morteza Najarian
- Department
of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2R3
- National
Institute for Nanotechnology, National Research Council Canada, Edmonton, Alberta, Canada, T6G 2G2
| | - Akhtar Bayat
- Department
of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2R3
- National
Institute for Nanotechnology, National Research Council Canada, Edmonton, Alberta, Canada, T6G 2G2
| | - Richard L. McCreery
- Department
of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2R3
- National
Institute for Nanotechnology, National Research Council Canada, Edmonton, Alberta, Canada, T6G 2G2
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46
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Wu BY, Sheng XQ, Fabregas R, Hao Y. Full-wave modeling of broadband near field scanning microwave microscopy. Sci Rep 2017; 7:16064. [PMID: 29167422 PMCID: PMC5700110 DOI: 10.1038/s41598-017-13937-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 10/03/2017] [Indexed: 11/09/2022] Open
Abstract
A three-dimensional finite element numerical modeling for the scanning microwave microscopy (SMM) setup is applied to study the full-wave quantification of the local material properties of samples. The modeling takes into account the radiation and scattering losses of the nano-sized probe neglected in previous models based on low-frequency assumptions. The scanning techniques of approach curves and constant height are implemented. In addition, we conclude that the SMM has the potential for use as a broadband dielectric spectroscopy operating at higher frequencies up to THz. The results demonstrate the accuracy of previous models. We draw conclusions in light of the experimental results.
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Affiliation(s)
- Bi-Yi Wu
- School of electronic engineering and computer science, Queen Mary University of London, London, E14NS, UK.,School of Information and Electronics, Beijing Institute of Technology, Beijing, 100081, China
| | - Xin-Qing Sheng
- School of Information and Electronics, Beijing Institute of Technology, Beijing, 100081, China
| | - Rene Fabregas
- Institut de Bioenginyeria de Catalunya (IBEC), c/Baldiri i Reixac 11-15, 08028, Barcelona, Spain.,Departament d'Enginyeries, Electrónica, Universitat de Barcelona, C/Martí i Franqués 1, 08028, Barcelona, Spain
| | - Yang Hao
- School of electronic engineering and computer science, Queen Mary University of London, London, E14NS, UK.
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47
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Zhang X, Costa PS, Hooper J, Miller DP, N'Diaye AT, Beniwal S, Jiang X, Yin Y, Rosa P, Routaboul L, Gonidec M, Poggini L, Braunstein P, Doudin B, Xu X, Enders A, Zurek E, Dowben PA. Locking and Unlocking the Molecular Spin Crossover Transition. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1702257. [PMID: 28846811 DOI: 10.1002/adma.201702257] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 06/19/2017] [Indexed: 06/07/2023]
Abstract
The Fe(II) spin crossover complex [Fe{H2 B(pz)2 }2 (bipy)] (pz = pyrazol-1-yl, bipy = 2,2'-bipyridine) can be locked in a largely low-spin-state configuration over a temperature range that includes temperatures well above the thermal spin crossover temperature of 160 K. This locking of the spin state is achieved for nanometer thin films of this complex in two distinct ways: through substrate interactions with dielectric substrates such as SiO2 and Al2 O3 , or in powder samples by mixing with the strongly dipolar zwitterionic p-benzoquinonemonoimine C6 H2 (-⋯ NH2 )2 (-⋯ O)2 . Remarkably, it is found in both cases that incident X-ray fluences then restore the [Fe{H2 B(pz)2 }2 (bipy)] moiety to an electronic state characteristic of the high spin state at temperatures of 200 K to above room temperature; that is, well above the spin crossover transition temperature for the pristine powder, and well above the temperatures characteristic of light- or X-ray-induced excited-spin-state trapping. Heating slightly above room temperature allows the initial locked state to be restored. These findings, supported by theory, show how the spin crossover transition can be manipulated reversibly around room temperature by appropriate design of the electrostatic and chemical environment.
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Affiliation(s)
- Xin Zhang
- Department of Physics and Astronomy, University of Nebraska, Lincoln, NE, 68588-0299, USA
| | - Paulo S Costa
- Department of Physics and Astronomy, University of Nebraska, Lincoln, NE, 68588-0299, USA
| | - James Hooper
- Department of Theoretical Chemistry, Faculty of Chemistry, Jagiellonian University, Krakow, 30-060, Poland
| | - Daniel P Miller
- Department of Chemistry, University of Buffalo, Buffalo, NY, 14260-3000, USA
| | - Alpha T N'Diaye
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Sumit Beniwal
- Department of Physics and Astronomy, University of Nebraska, Lincoln, NE, 68588-0299, USA
| | - Xuanyuan Jiang
- Department of Physics and Astronomy, University of Nebraska, Lincoln, NE, 68588-0299, USA
| | - Yuewei Yin
- Department of Physics and Astronomy, University of Nebraska, Lincoln, NE, 68588-0299, USA
| | - Patrick Rosa
- CNRS, Univ. Bordeaux, ICMCB, UPR 9048, F-33600, Pessac, France
| | - Lucie Routaboul
- Université de Strasbourg, CNRS, CHIMIE UMR 7177, Laboratoire de Chimie de Coordination, 4 rue Blaise Pascal, 67081, Strasbourg, France
| | - Mathieu Gonidec
- CNRS, Univ. Bordeaux, ICMCB, UPR 9048, F-33600, Pessac, France
| | - Lorenzo Poggini
- CNRS, Univ. Bordeaux, ICMCB, UPR 9048, F-33600, Pessac, France
| | - Pierre Braunstein
- Université de Strasbourg, CNRS, CHIMIE UMR 7177, Laboratoire de Chimie de Coordination, 4 rue Blaise Pascal, 67081, Strasbourg, France
| | - Bernard Doudin
- University of Strasbourg, CNRS, IPCMS UMR 7504, 23 rue du Loess, 67034, Strasbourg, France
| | - Xiaoshan Xu
- Department of Physics and Astronomy, University of Nebraska, Lincoln, NE, 68588-0299, USA
| | - Axel Enders
- Department of Physics and Astronomy, University of Nebraska, Lincoln, NE, 68588-0299, USA
- Physikalisches Institut, Universität Bayreuth, 95440, Bayreuth, Germany
| | - Eva Zurek
- Department of Chemistry, University of Buffalo, Buffalo, NY, 14260-3000, USA
| | - Peter A Dowben
- Department of Physics and Astronomy, University of Nebraska, Lincoln, NE, 68588-0299, USA
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48
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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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49
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Clement N, Fujiwara A. Molecular diodes: Breaking the Landauer limit. NATURE NANOTECHNOLOGY 2017; 12:725-726. [PMID: 28674458 DOI: 10.1038/nnano.2017.123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Affiliation(s)
- Nicolas Clement
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, 243-0198, Japan
| | - Akira Fujiwara
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, 243-0198, Japan
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50
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Chen X, Roemer M, Yuan L, Du W, Thompson D, Del Barco E, Nijhuis CA. Molecular diodes with rectification ratios exceeding 10 5 driven by electrostatic interactions. NATURE NANOTECHNOLOGY 2017; 12:797-803. [PMID: 28674457 DOI: 10.1038/nnano.2017.110] [Citation(s) in RCA: 144] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 05/03/2017] [Indexed: 06/07/2023]
Abstract
Molecular diodes operating in the tunnelling regime are intrinsically limited to a maximum rectification ratio R of ∼103. To enhance this rectification ratio to values comparable to those of conventional diodes (R ≥ 105) an alternative mechanism of rectification is therefore required. Here, we report a molecular diode with R = 6.3 × 105 based on self-assembled monolayers with Fc-C≡C-Fc (Fc, ferrocenyl) termini. The number of molecules (n(V)) involved in the charge transport changes with the polarity of the applied bias. More specifically, n(V) increases at forward bias because of an attractive electrostatic force between the positively charged Fc units and the negatively charged top electrode, but remains constant at reverse bias when the Fc units are neutral and interact weakly with the positively charged electrode. We successfully model this mechanism using molecular dynamics calculations.
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Affiliation(s)
- Xiaoping Chen
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Max Roemer
- 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
| | - Wei Du
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Damien Thompson
- Department of Physics, Bernal Institute, University of Limerick, Limerick V94 T9PX, Ireland
| | - 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 and Graphene Research Centre, National University of Singapore, 6 Science Drive 2, Singapore 117546, Singapore
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