1
|
Wang ML, Zhang GP, Fu XX, Wang CK. Low-bias conductance mechanism of diarylethene isomers: A first-principle study. CHINESE J CHEM PHYS 2020. [DOI: 10.1063/1674-0068/cjcp1911204] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Ming-lang Wang
- School of Physics and Electronics, Shandong Normal University, Jinan 250358, China
| | - Guang-ping Zhang
- School of Physics and Electronics, Shandong Normal University, Jinan 250358, China
| | - Xiao-xiao Fu
- School of Physics and Electronics, Shandong Normal University, Jinan 250358, China
| | - Chuan-kui Wang
- School of Physics and Electronics, Shandong Normal University, Jinan 250358, China
| |
Collapse
|
2
|
Wani IH, Jafri SHM, Warna J, Hayat A, Li H, Shukla VA, Orthaber A, Grigoriev A, Ahuja R, Leifer K. A sub 20 nm metal-conjugated molecule junction acting as a nitrogen dioxide sensor. NANOSCALE 2019; 11:6571-6575. [PMID: 30916070 DOI: 10.1039/c8nr08417c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The interaction of a gas molecule with a sensing material causes the highest change in the electronic structure of the latter, when this material consists of only a few atoms. If the sensing material consists of a short, conductive molecule, the sensing action can be furthermore probed by connecting such molecules to nanoelectrodes. Here, we report that NO2 molecules that adhere to 4,4'-biphenyldithiol (BPDT) bound to Au surfaces lead to a change of the electrical transmission of the BPDT. The related device shows reproducible, stable measurements and is so far the smallest (<20 nm) gas sensor. It demonstrates modulation of charge transport through molecules upon exposure to nitrogen dioxide down to concentrations of 55 ppb. We have evaluated several devices and exposure conditions and obtained a close to linear dependence of the sensor response on the gas concentration.
Collapse
Affiliation(s)
- Ishtiaq H Wani
- Applied Materials Science, Department of Engineering Sciences, Uppsala University, Box 534, Uppsala SE-75121, Sweden.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Wang K, Vezzoli A, Grace IM, McLaughlin M, Nichols RJ, Xu B, Lambert CJ, Higgins SJ. Charge transfer complexation boosts molecular conductance through Fermi level pinning. Chem Sci 2019; 10:2396-2403. [PMID: 30881668 PMCID: PMC6385675 DOI: 10.1039/c8sc04199g] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 01/02/2019] [Indexed: 11/21/2022] Open
Abstract
Interference features in the transmission spectra can dominate charge transport in metal-molecule-metal junctions when they occur close to the contact Fermi energy (E F). Here, we show that by forming a charge-transfer complex with tetracyanoethylene (TCNE) we can introduce new constructive interference features in the transmission profile of electron-rich, thiophene-based molecular wires that almost coincide with E F. Complexation can result in a large enhancement of junction conductance, with very efficient charge transport even at relatively large molecular lengths. For instance, we report a conductance of 10-3 G 0 (∼78 nS) for the ∼2 nm long α-quaterthiophene:TCNE complex, almost two orders of magnitude higher than the conductance of the bare molecular wire. As the conductance of the complexes is remarkably independent of features such as the molecular backbone and the nature of the contacts to the electrodes, our results strongly suggest that the interference features are consistently pinned near to the Fermi energy of the metallic leads. Theoretical studies indicate that the semi-occupied nature of the charge-transfer orbital is not only important in giving rise to the latter effect, but also could result in spin-dependent transport for the charge-transfer complexes. These results therefore present a simple yet effective way to increase charge transport efficiency in long and poorly conductive molecular wires, with important repercussions in single-entity thermoelectronics and spintronics.
Collapse
Affiliation(s)
- Kun Wang
- Department of Physics and Astronomy & NanoSEC , University of Georgia , 220 Riverbend Road , Athens , GA 30602 , USA .
| | - Andrea Vezzoli
- Department of Chemistry , University of Liverpool , Crown Street , Liverpool L69 7ZD , UK .
| | - Iain M Grace
- Department of Physics , Lancaster University , Lancaster LA1 4YB , UK .
| | - Maeve McLaughlin
- Department of Chemistry , University of Liverpool , Crown Street , Liverpool L69 7ZD , UK .
| | - Richard J Nichols
- Department of Chemistry , University of Liverpool , Crown Street , Liverpool L69 7ZD , UK .
| | - Bingqian Xu
- Department of Physics and Astronomy & NanoSEC , University of Georgia , 220 Riverbend Road , Athens , GA 30602 , USA .
- College of Engineering & NanoSEC , University of Georgia , 220 Riverbend Road , Athens , GA 30602 , USA
| | - Colin J Lambert
- Department of Physics , Lancaster University , Lancaster LA1 4YB , UK .
| | - Simon J Higgins
- Department of Chemistry , University of Liverpool , Crown Street , Liverpool L69 7ZD , UK .
| |
Collapse
|
4
|
Kumar N, Mandal SK. Design and application of a fluorogenic receptor for selective sensing of cations, small neutral molecules, and anions. NEW J CHEM 2018. [DOI: 10.1039/c8nj03998d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
An unprecedented single multi-analyte fluorogenic receptor, a sodium salt of N-(methyl-2-thiophenyl)-tyrosine (NaHTyrthio), is reported for the selective sensing of cations (Cu2+), small neutral molecules (nitrobenzene and aniline) and anions (F−) by variable spectral responses.
Collapse
Affiliation(s)
- Navnita Kumar
- Department of Chemical Sciences
- Indian Institute of Science Education and Research Mohali
- Mohali
- India
| | - Sanjay K. Mandal
- Department of Chemical Sciences
- Indian Institute of Science Education and Research Mohali
- Mohali
- India
| |
Collapse
|
5
|
Ismael AK, Al-Jobory A, Grace I, Lambert CJ. Discriminating single-molecule sensing by crown-ether-based molecular junctions. J Chem Phys 2017; 146:064704. [PMID: 28201900 DOI: 10.1063/1.4975771] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Crown-ether molecules are well known to selectively bind alkali atoms, so by incorporating these within wires, any change in electrical conductance of the wire upon binding leads to discriminating sensing. Using a density functional theory-based approach to quantum transport, we investigate the potential sensing capabilities of single-molecule junctions formed from crown ethers attached to anthraquinone units, which are in turn attached to gold electrodes via alkyl chains. We calculate the change in electrical conductance for binding of three different alkali ions (lithium, sodium, and potassium). Depending on the nature of the ionic analyte, the conductance is enhanced by different amounts. This change in electrical conductance is due to charge transfer from the ion to molecular wire causing the molecular resonances to shift closer to the electrode Fermi energy.
Collapse
Affiliation(s)
- Ali K Ismael
- Department of Physics, Lancaster University, Lancaster, United Kingdom
| | - Alaa Al-Jobory
- Department of Physics, Lancaster University, Lancaster, United Kingdom
| | - Iain Grace
- Department of Physics, Lancaster University, Lancaster, United Kingdom
| | - Colin J Lambert
- Department of Physics, Lancaster University, Lancaster, United Kingdom
| |
Collapse
|
6
|
Vezzoli A, Brooke RJ, Ferri N, Higgins SJ, Schwarzacher W, Nichols RJ. Single-Molecule Transport at a Rectifying GaAs Contact. NANO LETTERS 2017; 17:1109-1115. [PMID: 28079382 DOI: 10.1021/acs.nanolett.6b04663] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In most single- or few-molecule devices, the contact electrodes are simple ohmic resistors. Here we describe a new type of single-molecule device in which metal and semiconductor contact electrodes impart a function, namely, current rectification, which is then modified by a molecule bridging the gap. We study junctions with the structure Au STM tip/X/n-GaAs substrate, where "X" is either a simple alkanedithiol or a conjugated unit bearing thiol/methylthiol contacts, and we detect current jumps corresponding to the attachment and detachment of single molecules. From the magnitudes of the current jumps we can deduce values for the conductance decay constant with molecule length that agree well with values determined from Au/molecule/Au junctions. The ability to impart functionality to a single-molecule device through the properties of the contacts as well as through the properties of the molecule represents a significant extension of the single-molecule electronics "tool-box".
Collapse
Affiliation(s)
- Andrea Vezzoli
- Department of Chemistry, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom
| | - Richard J Brooke
- H. H. Wills Physics Laboratory, University of Bristol , Tyndall Avenue, Bristol BS8 1TL, United Kingdom
| | - Nicolò Ferri
- Department of Chemistry, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom
| | - Simon J Higgins
- Department of Chemistry, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom
| | - Walther Schwarzacher
- H. H. Wills Physics Laboratory, University of Bristol , Tyndall Avenue, Bristol BS8 1TL, United Kingdom
| | - Richard J Nichols
- Department of Chemistry, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom
| |
Collapse
|
7
|
Vezzoli A, Grace I, Brooke C, Wang K, Lambert CJ, Xu B, Nichols RJ, Higgins SJ. Gating of single molecule junction conductance by charge transfer complex formation. NANOSCALE 2015; 7:18949-55. [PMID: 26510687 DOI: 10.1039/c5nr04420k] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The solid-state structures of organic charge transfer (CT) salts are critical in determining their mode of charge transport, and hence their unusual electrical properties, which range from semiconducting through metallic to superconducting. In contrast, using both theory and experiment, we show here that the conductance of metal |single molecule| metal junctions involving aromatic donor moieties (dialkylterthiophene, dialkylbenzene) increase by over an order of magnitude upon formation of charge transfer (CT) complexes with tetracyanoethylene (TCNE). This enhancement occurs because CT complex formation creates a new resonance in the transmission function, close to the metal contact Fermi energy, that is a signal of room-temperature quantum interference.
Collapse
Affiliation(s)
- Andrea Vezzoli
- Department of Chemistry, Donnan and Robert Robinson Laboratories, University of Liverpool, Liverpool L69 7ZD, UK.
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Liao J, Blok S, van der Molen SJ, Diefenbach S, Holleitner AW, Schönenberger C, Vladyka A, Calame M. Ordered nanoparticle arrays interconnected by molecular linkers: electronic and optoelectronic properties. Chem Soc Rev 2015; 44:999-1014. [DOI: 10.1039/c4cs00225c] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Arrays of metal nanoparticles in an organic matrix have attracted a lot of interest due to their diverse electronic and optoelectronic properties.
Collapse
Affiliation(s)
- Jianhui Liao
- Key Laboratory for the Physics and Chemistry of Nanodevices
- Department of Electronics
- Peking University
- Beijing 100871
- China
| | - Sander Blok
- Leiden Institute of Physics
- Universiteit Leiden
- 2333 CA Leiden
- Netherlands
| | | | - Sandra Diefenbach
- Walter Schottky Institut and Physik-Department
- Technische Universtität München
- 85748 Garching
- Germany
- Nanosystems Initiative Munich (NIM)
| | - Alexander W. Holleitner
- Walter Schottky Institut and Physik-Department
- Technische Universtität München
- 85748 Garching
- Germany
- Nanosystems Initiative Munich (NIM)
| | | | - Anton Vladyka
- Department of Physics
- Universität Basel
- 4056 Basel
- Switzerland
| | - Michel Calame
- Department of Physics
- Universität Basel
- 4056 Basel
- Switzerland
- Swiss Nanoscience Institute
| |
Collapse
|