Engineering the Thermopower of C60 Molecular Junctions
- 1 April 2013
- journal article
- research article
- Published by American Chemical Society (ACS) in Nano Letters
- Vol. 13 (5), 2141-2145
- https://doi.org/10.1021/nl400579g
Abstract
We report the measurement of conductance and thermopower of C60 molecular junctions using a scanning tunneling microscope (STM). In contrast to previous measurements, we use the imaging capability of the STM to determine precisely the number of molecules in the junction and measure thermopower and conductance continuously and simultaneously during formation and breaking of the molecular junction, achieving a complete characterization at the single-molecule level. We find that the thermopower of C60 dimers formed by trapping a C60 on the tip and contacting an isolated C60 almost doubles with respect to that of a single C60 and is among the highest values measured to date for organic materials. Density functional theory calculations show that the thermopower and the figure of merit continue increasing with the number of C60 molecules, demonstrating the enhancement of thermoelectric preformance by manipulation of intermolecular interactions.Keywords
This publication has 18 references indexed in Scilit:
- Unambiguous One-Molecule Conductance Measurements under Ambient ConditionsNano Letters, 2011
- The Nature of Transport Variations in Molecular Heterojunction ElectronicsNano Letters, 2009
- Giant thermopower and figure of merit in single-molecule devicesPhysical Review B, 2009
- Probing the Chemistry of Molecular Heterojunctions Using ThermoelectricityNano Letters, 2008
- Conductance of individualmolecules measured with controllable gold electrodesPhysical Review B, 2007
- Thermoelectricity in Molecular JunctionsScience, 2007
- Controlled Contact to aMoleculePhysical Review Letters, 2007
- Towards molecular spintronicsNature Materials, 2005
- The SIESTA method forab initioorder-Nmaterials simulationJournal of Physics: Condensed Matter, 2002
- Atomic-Sized Metallic Contacts: Mechanical Properties and Electronic TransportPhysical Review Letters, 1996