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The adsorption of 4,4ʹ-bipyridine at a Cd(0001)|ionic liquid interface – The descent into disorder. Electrochem commun 2023. [DOI: 10.1016/j.elecom.2023.107451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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2
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Order beyond a monolayer: The story of two self-assembled 4,4′-bipyridine layers on the Sb(111) | ionic liquid interface. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.140468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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3
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Oyamada N, Minamimoto H, Murakoshi K. Room-Temperature Molecular Manipulation via Plasmonic Trapping at Electrified Interfaces. J Am Chem Soc 2022; 144:2755-2764. [PMID: 35107293 DOI: 10.1021/jacs.1c12213] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
For the motion control of individual molecules at room temperature, optical tweezers could be one of the best approaches to realize desirable selectivity with high resolution in time and space. Because of physical limitations due to the thermal fluctuation, optical manipulation of small molecules at room temperature is still a challenging subject. The difficulty of the manipulation also emerged from the variation of molecular polarizability depending on the choice of molecules as well as the molecular orientation to the optical field. In this article, we have demonstrated plasmonic optical trapping of small size molecules with less than 1 nm at the gap of a single metal nanodimer immersed in an electrolyte solution. In situ electrochemical surface-enhanced Raman scattering measurements prove that a plasmonic structure under electrochemical potential control realizes not only the selective molecular condensation but also the formation of unique mixed molecular phases which is distinct from those under a thermodynamic equilibrium. Through detailed analyses of optical trapping behavior, we established the methodology of plasmonic optical trapping to create the novel adsorption isotherm under applying an optical force at electrified interfaces.
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Affiliation(s)
- Nobuaki Oyamada
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Hiro Minamimoto
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Kei Murakoshi
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
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4
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Oyamada N, Minamimoto H, Wakisaka Y, Murakoshi K. Determination of Molecular Orientation in Bi-analyte Mono-molecule Layer through Electrochemical Surface-enhanced Raman Scattering Measurements. CHEM LETT 2019. [DOI: 10.1246/cl.190282] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Nobuaki Oyamada
- Department of Chemistry, Faculty of Science, Hokkaido University, North 10 West 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Hiro Minamimoto
- Department of Chemistry, Faculty of Science, Hokkaido University, North 10 West 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Yumi Wakisaka
- Department of Chemistry, Faculty of Science, Hokkaido University, North 10 West 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Kei Murakoshi
- Department of Chemistry, Faculty of Science, Hokkaido University, North 10 West 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
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Isshiki Y, Fujii S, Nishino T, Kiguchi M. Impact of junction formation processes on single molecular conductance. Phys Chem Chem Phys 2018; 20:7947-7952. [DOI: 10.1039/c8cp00317c] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have investigated the electric conductance and atomic structure of single molecular junctions of pyrazine (Py), 4,4′-bipyridine (BiPy), fullerene (C60), and 1,4-diaminobutane (DAB).
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Affiliation(s)
- Y. Isshiki
- Department of Chemistry
- Tokyo Institute of Technology
- Tokyo
- Japan
| | - S. Fujii
- Department of Chemistry
- Tokyo Institute of Technology
- Tokyo
- Japan
| | - T. Nishino
- Department of Chemistry
- Tokyo Institute of Technology
- Tokyo
- Japan
| | - M. Kiguchi
- Department of Chemistry
- Tokyo Institute of Technology
- Tokyo
- Japan
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7
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Pikma P, Kasuk H, Oll O, Ivaništšev V, Romann T, Grozovski V, Lust K, Lust E. Adsorption of 4,4′−bipyridine on the Cd(0001) single crystal electrode surface. Electrochim Acta 2015. [DOI: 10.1016/j.electacta.2015.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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8
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Grozovski V, Ivaništšev V, Kasuk H, Romann T, Lust E. Balance of the interfacial interactions of 4,4′-bipyridine at Bi(111) surface. Electrochim Acta 2014. [DOI: 10.1016/j.electacta.2013.12.047] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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10
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Baghernejad M, Manrique DZ, Li C, Pope T, Zhumaev U, Pobelov I, Moreno-García P, Kaliginedi V, Huang C, Hong W, Lambert C, Wandlowski T. Highly-effective gating of single-molecule junctions: an electrochemical approach. Chem Commun (Camb) 2014; 50:15975-8. [DOI: 10.1039/c4cc06519k] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We report an electrochemical gating approach with ∼100% efficiency to tune the conductance of single-molecule 4,4′-bipyridine junctions.
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Affiliation(s)
- Masoud Baghernejad
- Department of Chemistry and Biochemistry
- University of Bern
- Bern, Switzerland
| | | | - Chen Li
- Department of Chemistry and Biochemistry
- University of Bern
- Bern, Switzerland
| | - Thomas Pope
- Department of Physics
- Lancaster University
- Lancaster LA1 4YB, United Kingdom
| | - Ulmas Zhumaev
- Department of Chemistry and Biochemistry
- University of Bern
- Bern, Switzerland
| | - Ilya Pobelov
- Department of Chemistry and Biochemistry
- University of Bern
- Bern, Switzerland
| | | | | | - Cancan Huang
- Department of Chemistry and Biochemistry
- University of Bern
- Bern, Switzerland
| | - Wenjing Hong
- Department of Chemistry and Biochemistry
- University of Bern
- Bern, Switzerland
| | - Colin Lambert
- Department of Physics
- Lancaster University
- Lancaster LA1 4YB, United Kingdom
| | - Thomas Wandlowski
- Department of Chemistry and Biochemistry
- University of Bern
- Bern, Switzerland
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11
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Chen S, Huang Y, Yau S, Chen CJ, Lai CK. In situ scanning tunneling microscopy of 5-(Dodecyloxy)-2-(5-(4-(pentyloxy)phenyl)-1H-pyrazol-3-yl)phenol adsorbed on Au(111) electrode. J Electroanal Chem (Lausanne) 2012. [DOI: 10.1016/j.jelechem.2011.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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12
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Higashi T, Shigemitsu Y, Sagara T. Faradaic phase transition of dibenzyl viologen on an HOPG electrode surface studied by in situ electrochemical STM and electroreflectance spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:13910-13917. [PMID: 21955062 DOI: 10.1021/la202746y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Phase transitions of an adsorption layer of dibenzyl viologen (dBV) as a typical diaryl viologen on a basal plane of a highly oriented pyrolytic graphite (HOPG) electrode are described using voltammetry, in situ electrochemical scanning tunneling microscopy (EC-STM), and electroreflectance (ER) spectroscopy. A monolayer redox process at less negative potential than the bulk redox process was found to be the first-order faradaic phase transition between a gaslike adsorption layer of dication (dBV(2+)) and a 2D condensed monolayer of radical cation (dBV(•+)). Comparison of the results of cyclic voltammetry and potential step chronoamperometry was made with those of heptyl viologen (HV), which also undergoes a faradaic phase transition of the first order. It suggested that the contribution of intermolecular π-π interaction between benzyl groups of dBV to the phase transition is minor and apparently equivalent to interchain interaction between the heptyl chains of HV. In situ EC-STM images of the 2D condensed monolayer demonstrated stripe patterns of the rows of dBV(•+) molecules forming 3-fold rotationally symmetric domains. The results of the ER measurements also revealed that the orientation of the longitudinal molecular axis of the bipyridinium moiety of dBV(•+) molecules lying flat on the HOPG electrode surface, most likely with a side-on configuration.
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Affiliation(s)
- Tomohiro Higashi
- Department of Molecular Science, Graduate School of Science and Technology, Nagasaki University, Nagasaki 852-8521, Japan
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Röefzaad M, Jiang M, Zamlynny V, Wandelt K. Potential dependent structure transitions of heptyl viologen layers on Cu(100) studied by in situ STM and IRRAS. J Electroanal Chem (Lausanne) 2011. [DOI: 10.1016/j.jelechem.2011.07.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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14
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Dora SK, Wandelt K. Recrystallization of tubules from natural lotus (Nelumbo nucifera) wax on a Au(111) surface. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2011; 2:261-267. [PMID: 21977438 PMCID: PMC3148047 DOI: 10.3762/bjnano.2.30] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Accepted: 04/26/2011] [Indexed: 05/29/2023]
Abstract
We present here the first results on the self-assembly of tubules of natural wax from lotus leaves on a single crystal Au(111) surface. A comparison of the tubule growth on Au(111) to that on HOPG is discussed. Although the tubule formation on both Au(111) and HOPG takes place on an intermediate wax film which should mask the substrate properties, the tubule orientations differ. In contrast to a vertical tubule orientation on HOPG, the tubules lie flat on Au(111). Taking into account the physical properties of HOPG and Au(111), we put forward a hypothesis which can explain the different tubule orientations on both substrates.
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Affiliation(s)
- Sujit Kumar Dora
- Institute of Physical and Theoretical Chemistry, Bonn University, Wegelerstrasse 12, 53115 Bonn, Germany
| | - Klaus Wandelt
- Institute of Physical and Theoretical Chemistry, Bonn University, Wegelerstrasse 12, 53115 Bonn, Germany
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15
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Hermes JP, Sander F, Peterle T, Cioffi C, Ringler P, Pfohl T, Mayor M. Direct control of the spatial arrangement of gold nanoparticles in organic-inorganic hybrid superstructures. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2011; 7:920-929. [PMID: 21394907 DOI: 10.1002/smll.201002101] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Indexed: 05/30/2023]
Abstract
The directed assembly of gold nanoparticles is essential for their use in many kinds of applications, such as electronic devices, biological labels, and sensors. Herein an atomic alteration in the molecular structure of ligand-stabilized gold nanoparticles that can shift the interparticle distance up to 1 nm upon covalent coupling to organic-inorganic superstructures is presented. Gold nanoparticles are stabilized by two octadentate thioether ligands and have a mean diameter of 1.1 nm. The ligands contain a central rigid rod varying in length and terminally functionalized with a protected acetylene. The two peripheral functional groups on each particle enable the directed assembly of nanoparticles to dimers, trimers, and tetramers by oxidative acetylene coupling. This is a wet chemical protocol resulting in covalently bound nanoparticles. These organic-inorganic hybrid superstructures are analyzed by transmission electron microscopy, small angle X-ray scattering, and UV/vis spectroscopy. The focus of the comparison here is the subunit, which is anchoring the bridgehead, either a pyridine or benzene moiety. The pyridine-based ligands reflect the calculated length of the rigid-rod spacer in their interparticle distances in the obtained hybrid structures. This suggests a perpendicular arrangement that results from the coordination of the pyridine's lone pair to the gold surface. An atomic variation in the ligand's center leads to smaller interparticle distances in the case of hybrid structures obtained from benzene ligands. This large difference in the spatial arrangement suggests a tangential arrangement of the interparticle bridging structure in the latter case. Consequently a rather flat arrangement parallel to the particle surface must be assumed for the central benzene unit of the benzene-based ligand.
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Affiliation(s)
- Jens P Hermes
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
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16
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Charge Transport in Single Molecular Junctions at the Solid/Liquid Interface. Top Curr Chem (Cham) 2011; 313:121-88. [DOI: 10.1007/128_2011_238] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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17
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Heimel G, Rissner F, Zojer E. Modeling the electronic properties of pi-conjugated self-assembled monolayers. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2010; 22:2494-513. [PMID: 20414885 DOI: 10.1002/adma.200903855] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The modification of electrode surfaces by depositing self-assembled monolayers (SAMs) provides the possibility for controlled adjustment of various key parameters in organic and molecular electronic devices. Most important among them are the work function of the electrode and the relative alignment of its Fermi level with the conducting states in the SAM itself and with those in a subsequently deposited organic semiconductor. For the efficient application of such interface modifications it is crucial to reach a proper understanding of the relation between the chemical structure of a molecule, its molecular electronic characteristics, and the properties of the SAM formed by such molecules. Over the past years, quantum-mechanical calculations have proven to be a valuable tool for reaching a fundamental understanding of the relevant structure-property relations. Here, we provide a review over the field and report on recent progress in the modeling of the interfacial electronic properties of pi-conjugated SAMs. In addition to the insight that can be gained from simple electrostatic considerations, we focus on the quantum-mechanical description of the roles played by substituents, molecular backbones, chemical anchoring groups, and the packing density of molecules on the surface. Furthermore, we explicitly address the energy-level alignment at the interface between a prototypical organic semiconductor and a SAM-covered metal electrode and describe an approach suitable for extending the metallic character of the substrate onto the monolayer.
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Affiliation(s)
- Georg Heimel
- Institut für Physik, Humboldt-Universität zu Berlin, Newtonstrasse 15, 12489 Berlin, Germany.
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Jiang M, Sak E, Gentz K, Krupski A, Wandelt K. Redox activity and structural transition of heptyl viologen adlayers on Cu(100). Chemphyschem 2010; 11:1542-9. [PMID: 20235114 DOI: 10.1002/cphc.200900964] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The redox behaviour and potential-dependent adsorption structure of heptyl viologen (1,1'-diheptyl-4,4'-bipyridinium dichloride, DHV(2+)) on a Cu(100) electrode was investigated in a chloride-containing electrolyte solution by cyclic voltammetry (CV) and in situ electrochemical scanning tunneling microscopy (EC-STM). The dicationic DHV molecules generate a few pairs of current waves in CV measurements which are ascribed to two typical one-electron transfer steps. STM images obtained in a KCl-containing electrolyte solution disclose a well-ordered c(2x2) chloride adlayer on a Cu(100) electrode surface. After injecting DHV(2+) molecules into the KCl electrolyte solution, a highly ordered 2D "dot-array" structure in STM images emerges on the c(2x2)-Cl modified Cu(100) electrode surface. DHV(2+) molecules spontaneously arrange themselves with their molecular planes facing the electrode surface and their long molecular axis parallel to the step edge. Such adsorption structure can be described by mirror domains and rotational domains which stably exist between 200 mV and -100 mV. One-electron reduction of the dications DHV(2+) around -150 mV causes a phase transition from a 'dot-array' assembly to a stripe pattern formed by DHV(*+) radical monocations in STM images which has a bilayer structure. With a further decrease of the applied electrode potential, the structure of the DHV(*+) adlayer undergoes a change from a loose stripe phase to a more compact stripe phase, a subsequent decay of the compact structure, and finally the formation of a new dimer phase. A further electron transfer reaction at -400 mV causes the formation of an amorphous phase on the chloride free electrode surface. In a reverse anodic sweep, the reproduction of the ordered DHV(*+) stacking phase occurs again on top of the chloride lattice.
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Affiliation(s)
- Min Jiang
- Institue of Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115 Bonn, Germany
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19
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Grunder S, Huber R, Wu S, Schönenberger C, Calame M, Mayor M. Oligoaryl Cruciform Structures as Model Compounds for Coordination-Induced Single-Molecule Switches. European J Org Chem 2010. [DOI: 10.1002/ejoc.200901150] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Tsay SL, Tsay JS, Fu TY, Broekmann P, Sagara T, Wandelt K. Molecular structures of dicarboxylated viologens on a Cu(100) surface during an ongoing charge transfer reaction. Phys Chem Chem Phys 2010; 12:14950-9. [DOI: 10.1039/c0cp00865f] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Marichev V. Kinetics of chloride ion adsorption on stainless alloys by in situ contact electric resistance technique. Electrochim Acta 2008. [DOI: 10.1016/j.electacta.2008.04.067] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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22
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Kallip S, Kasuk H, Grozovski V, Möller P, Lust E. Adsorption of camphor and 2,2′-bipyridine on Bi(111) electrode surface. Electrochim Acta 2008. [DOI: 10.1016/j.electacta.2007.10.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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23
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Korzeniewski C. Recent Advances in in‐situ Infrared Spectroscopy and Applications in Single‐Crystal Electrochemistry and Electrocatalysis. ACTA ACUST UNITED AC 2008. [DOI: 10.1002/9783527616817.ch7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Wu X, Li Q, Huang J, Yang J. Nonequilibrium electronic transport of 4,4'-bipyridine molecular junction. J Chem Phys 2007; 123:184712. [PMID: 16292926 DOI: 10.1063/1.2102902] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The electronic transport properties of a 4,4'-bipyridine molecule sandwiched between two Au(111) surfaces are studied with a fully self-consistent nonequilibrium Green's-function method combined with the density-functional theory. The 4,4'-bipyridine molecule prefers to adsorb near the hollow site of the Au(111) surface and distorts slightly. The modifications on the electronic structure of the molecule due to the presence of the electrodes are described by the renormalized molecular orbitals, which correspond well to the calculated transmission peaks. The average Fermi level lies close to the lowest unoccupied renormalized molecular orbital, which determines the electronic transport property of the molecular junction under a small bias voltage. The total transmission is contributed by a single channel. The transmission peaks shift with the applied bias voltage, and this behavior depends on the spatial distribution of the renormalized molecular orbitals and the voltage drop along the molecular junction. The shape of the calculated conductance curve of the equilibrium geometric configuration reproduces the main feature of the experimental results, but the value is larger than the measured data by about 6 times. Good agreement with the experimental measurements can be obtained by elongating the molecular junction. The electronic transport behaviors depend strongly on the interface configuration.
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Affiliation(s)
- Xiaojun Wu
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
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Sawai Y, Takimoto B, Nabika H, Ajito K, Murakoshi K. Observation of a small number of molecules at a metal nanogap arrayed on a solid surface using surface-enhanced Raman scattering. J Am Chem Soc 2007; 129:1658-62. [PMID: 17284005 DOI: 10.1021/ja067034c] [Citation(s) in RCA: 182] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In situ Raman spectroscopic measurements with 785 nm excitation were carried out in aqueous solutions containing bipyridine derivatives. Intense Raman signals were observed when the Ag dimer structure was optimized. The SERS activity was dependent upon on the structure of the Ag dimer with a distinct gap distance, suggesting that the intense SERS originates from the gap part of the dimer. Characteristic time-dependent spectral changes were observed. Not only a spectrum which was the superposition of two bipyridine spectra but also spectra which can be assigned to one of the bipyridine derivatives were frequently observed. Observation using solutions with different concentrations proved that the spectra originated from very small numbers of molecules at the active SERS site of the dimer.
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Affiliation(s)
- Yoshitaka Sawai
- Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
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Diao YX, Han MJ, Wan LJ, Itaya K, Uchida T, Miyake H, Yamakata A, Osawa M. Adsorbed structures of 4,4'-bipyridine on Cu(111) in acid studied by STM and IR. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:3640-6. [PMID: 16584238 DOI: 10.1021/la052765w] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The adsorption of 4,4'-bipyridine (BiPy) on Cu(111) has been investigated in 0.1 M HClO4 by cyclic voltammetry, electrochemical scanning tunneling microscopy (STM), and surface-enhanced infrared adsorption spectroscopy (SEIRAS). Cyclic voltammetry showed the double layer region extending from -0.2 to 0.26 V and a pair of redox waves superposing on hydrogen evolution wave at more negative potentials. Diprotonated BiPy, BiPyH2(2+), is adsorbed flat on the Cu(111) (1 x 1) surface and forms a well-ordered monolayer with a (3 x 4) symmetry in the double-layer potential region. At more negative potential, BiPyH2(2+) is reduced to its monocation radical, BiPyH2(*+), and forms another well-ordered structure in which the radicals are stacked in molecular rows with a face-to-face self-dimer as the building unit. The SEIRA spectra of both BiPyH2(2+) and BiPyH2(*+) are dominated by gerade modes which should be IR-inactive for the centrosymmetric species. The breakdown of the selection rule of IR absorption is ascribed to the vibronic coupling associated with charge transfer between BiPyH2(2+) and the surface and between the radicals.
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Affiliation(s)
- Yu-Xia Diao
- Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
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Shih WY, Yang J. A New Infrared Spectroelectrochemical Cell for the Detection of Species Generated by Platinum and Screen-Printed Carbon Electrodes. ELECTROANAL 2006. [DOI: 10.1002/elan.200503398] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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28
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Madueño R, Pineda T, Sevilla J, Blázquez M. The kinetics of the dissolution of 6-mercaptopurine self-assembled monolayers on Au(111) and Hg electrodes. J Electroanal Chem (Lausanne) 2005. [DOI: 10.1016/j.jelechem.2004.10.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Hou S, Zhang J, Li R, Ning J, Han R, Shen Z, Zhao X, Xue Z, Wu Q. First-principles calculation of the conductance of a single 4,4 bipyridine molecule. NANOTECHNOLOGY 2005; 16:239-244. [PMID: 21727429 DOI: 10.1088/0957-4484/16/2/010] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The conductance of a single 4,4 bipyridine (44BPD) molecule connected to two gold electrodes is calculated using a density functional theory based Green function method. The atomic geometry of such a molecular junction is constructed from the optimized structure of a gold trimer-44BPD-gold trimer complex. Resonant conduction is the main feature of its transport properties. The magnitude of the transmission coefficient at the Fermi level is determined to be T = 1.01 × 10(-2), which is in excellent agreement with the experimental value. The dependence of the transmission on the Au-N bond length and the torsion angle is also discussed.
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Affiliation(s)
- Shimin Hou
- Department of Electronics, Peking University, Beijing 100871, People's Republic of China
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30
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Gómez L, Ruiz JJ, Camacho L, Rodríguez-Amaro R. Chronoamperometric study of the films formed by 4,4'-bipyridyl cation radical salts on mercury in the presence of iodide ions: consecutive two-dimensional phase transitions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:369-374. [PMID: 15620326 DOI: 10.1021/la0481703] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This paper reports a new mathematical model for consecutive two-dimensional phase transitions that accounts for the chronoamperometric behavior observed in the formation of electrochemical phases by 4,4'-bipyridyl cation radical (BpyH(2)(*)(+)) on mercury in aqueous iodide solutions. Also, a new interpretation for the induction time is proposed.
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Affiliation(s)
- L Gómez
- Departamento de Química Física y Termodinámica Aplicada, Universidad de Córdoba, Campus de Rabanales, Edificio C3, E-14014 Córdoba, Spain
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Double potential step chronoreflectometry approach to bi-stable potential region of the faradaic phase transition of heptyl viologen at a HOPG electrode. J Electroanal Chem (Lausanne) 2004. [DOI: 10.1016/j.jelechem.2003.12.049] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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32
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Haiss W, Nichols RJ, Higgins SJ, Bethell D, Höbenreich H, Schiffrin DJ. Wiring nanoparticles with redox molecules. Faraday Discuss 2004; 125:179-94; discussion 195-219. [PMID: 14750672 DOI: 10.1039/b303214k] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Gold nanoparticles were used to make electrical contact to redox-active organic molecules. Viologen based dithiols were self-assembled from solution on Au(111) for use as tethers to attach nanoparticles to a conducting substrate. The topography and electrical properties of the resulting films were investigated by STM and STS and the orientation of these linkers was investigated by FTIR. Surface coverage increased with increasing reaction time, resulting in a change of film orientation from a flat to a more upright standing conformation. Gold nanoparticles attached to these self-assembled films were characterised by STM. It was possible to isolate a single redox-active molecule in an alkanethiol matrix and by subsequent attachment of a single gold nanoparticle the electrical properties of single wired molecules could be investigated. This method allowed the measurement of the conductivity of single molecules connecting a nanoparticle to the substrate chemically, thus forming stable electrical contacts at both ends.
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Affiliation(s)
- Wolfgang Haiss
- Centre for Nanoscale Science, Chemistry Department, University of Liverpool, Liverpool, UK L69 7ZD
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