1
|
Zhou P, Qiao X, Milan DC, Higgins SJ, Vezzoli A, Nichols RJ. Enhanced charge transport across molecule-nanoparticle-molecule sandwiches. Phys Chem Chem Phys 2023; 25:7176-7183. [PMID: 36810584 DOI: 10.1039/d2cp05525b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
The electrical properties of large area molecular devices consisting of gold nanoparticles (GNPs) sandwiched between a double layer of alkanedithiol linkers have been examined. These devices have been fabricated by a facile bottom-up assembly in which an alkanedithiol monolayer is first self-assembled on an underlying gold substrate followed by nanoparticle adsorption and then finally assembly of the top alkanedithiol layer. These devices are then sandwiched between the bottom gold substrates and a top eGaIn probe contact and current-voltage (I-V) curves recorded. Devices have been fabricated with 1,5-pentanedithiol, 1,6-hexanedithiol, 1,8-octanedithiol and 1,10-decanedithiol linkers. In all cases the electrical conductance of the double SAM junctions with GNPs is higher than the corresponding and much thinner single alkanedithiol SAM. Competing models for this enhanced conductance are discussed and it is suggested to have a topological origin arising from how the devices assemble or structure during the fabrication, which gives more efficient cross device electron transport pathways without the GNPs producing short circuits.
Collapse
Affiliation(s)
- P Zhou
- Yangzhou Polytechnic Institute, No. 199, Huayang West Road, Yangzhou City, Jiangsu Province, China.,Department of Chemistry, University of Liverpool, Crown St, Liverpool, L69 7ZD, UK.
| | - X Qiao
- Department of Chemistry, University of Liverpool, Crown St, Liverpool, L69 7ZD, UK.
| | - D C Milan
- Department of Chemistry, University of Liverpool, Crown St, Liverpool, L69 7ZD, UK.
| | - S J Higgins
- Department of Chemistry, University of Liverpool, Crown St, Liverpool, L69 7ZD, UK.
| | - A Vezzoli
- Department of Chemistry, University of Liverpool, Crown St, Liverpool, L69 7ZD, UK.
| | - R J Nichols
- Department of Chemistry, University of Liverpool, Crown St, Liverpool, L69 7ZD, UK.
| |
Collapse
|
2
|
Herrer L, Ismael A, Martín S, Milan DC, Serrano JL, Nichols RJ, Lambert C, Cea P. Single molecule vs. large area design of molecular electronic devices incorporating an efficient 2-aminepyridine double anchoring group. Nanoscale 2019; 11:15871-15880. [PMID: 31414113 DOI: 10.1039/c9nr05662a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
When a molecule is bound to external electrodes by terminal anchor groups, the latter are of paramount importance in determining the electrical conductance of the resulting molecular junction. Here we explore the electrical properties of a molecule with bidentate anchor groups, namely 4,4'-(1,4-phenylenebis(ethyne-2,1-diyl))bis(pyridin-2-amine), in both large area devices and at the single molecule level. We find an electrical conductance of 0.6 × 10-4G0 and 1.2 × 10-4G0 for the monolayer and for the single molecule, respectively. These values are approximately one order of magnitude higher than those reported for monodentate materials having the same molecular skeleton. A combination of theory and experiments is employed to understand the conductance of monolayer and single molecule electrical junctions featuring this new multidentate anchor group. Our results demonstrate that the molecule has a tilt angle of 30° with respect to the normal to the surface in the monolayer, while the break-off length in the single molecule junction occurs for molecules having a tilt angle estimated as 40°, which would account for the difference in their conductance values per molecule. The bidentate 2-aminepyridine anchor is of general interest as a contact group, since this terminal functionalized aromatic ring favours binding of the adsorbate to the metal contact resulting in enhanced conductance values.
Collapse
Affiliation(s)
- L Herrer
- Departamento de Química Física, Facultad de Ciencias, Universidad de Zaragoza, 50009, Zaragoza, Spain. and Instituto de Nanociencia de Aragón (INA) and Laboratorio de Microscopias Avanzadas (LMA), Edificio I+D Campus Río Ebro, Universidad de Zaragoza, C/Mariano Esquillor, s/n, 50018 Zaragoza, Spain.
| | - A Ismael
- Department of Physics, University of Lancaster, Lancaster, LA1 4YB, UK. and Department of Physics, College of Education for Pure Science, Tikrit University, Tikrit, Iraq
| | - S Martín
- Departamento de Química Física, Facultad de Ciencias, Universidad de Zaragoza, 50009, Zaragoza, Spain. and Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK.
| | - D C Milan
- Instituto de Ciencia de Materiales de Aragón (ICMA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - J L Serrano
- Instituto de Nanociencia de Aragón (INA) and Laboratorio de Microscopias Avanzadas (LMA), Edificio I+D Campus Río Ebro, Universidad de Zaragoza, C/Mariano Esquillor, s/n, 50018 Zaragoza, Spain. and Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK. and Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Zaragoza, 50009, Zaragoza, Spain
| | - R J Nichols
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK.
| | - C Lambert
- Department of Physics, University of Lancaster, Lancaster, LA1 4YB, UK.
| | - P Cea
- Departamento de Química Física, Facultad de Ciencias, Universidad de Zaragoza, 50009, Zaragoza, Spain. and Instituto de Nanociencia de Aragón (INA) and Laboratorio de Microscopias Avanzadas (LMA), Edificio I+D Campus Río Ebro, Universidad de Zaragoza, C/Mariano Esquillor, s/n, 50018 Zaragoza, Spain. and Instituto de Ciencia de Materiales de Aragón (ICMA), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| |
Collapse
|
3
|
Rubio-Verdú C, Sáenz-Arce G, Martinez-Asencio J, Milan DC, Moaied M, Palacios JJ, Caturla MJ, Untiedt C. Graphene flakes obtained by local electro-exfoliation of graphite with a STM tip. Phys Chem Chem Phys 2017; 19:8061-8068. [DOI: 10.1039/c6cp07236d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Graphene flakes obtained by electro-exfoliation of graphite with a STM tip at the edge of a terrace: experiments, ab initio calculations and molecular dynamics simulations.
Collapse
Affiliation(s)
- C. Rubio-Verdú
- Departamento de Física Aplicada
- Facultad de Ciencias
- Universidad de Alicante
- Alicante
- Spain
| | - G. Sáenz-Arce
- Departamento de Física Aplicada
- Facultad de Ciencias
- Universidad de Alicante
- Alicante
- Spain
| | - J. Martinez-Asencio
- Departamento de Física Aplicada
- Facultad de Ciencias
- Universidad de Alicante
- Alicante
- Spain
| | - D. C. Milan
- Departamento de Física Aplicada
- Facultad de Ciencias
- Universidad de Alicante
- Alicante
- Spain
| | - M. Moaied
- Departamento de Física de la Materia Condensada
- Instituto de Ciencia de Materiales Nicolás Cabrera (INC)
- and Condensed Matter Physics Center (IFIMAC)
- Universidad Autónoma de Madrid
- 28049 Madrid
| | - J. J. Palacios
- Departamento de Física de la Materia Condensada
- Instituto de Ciencia de Materiales Nicolás Cabrera (INC)
- and Condensed Matter Physics Center (IFIMAC)
- Universidad Autónoma de Madrid
- 28049 Madrid
| | - M. J. Caturla
- Departamento de Física Aplicada
- Facultad de Ciencias
- Universidad de Alicante
- Alicante
- Spain
| | - C. Untiedt
- Departamento de Física Aplicada
- Facultad de Ciencias
- Universidad de Alicante
- Alicante
- Spain
| |
Collapse
|