Efficiency of thermoelectric energy conversion in biphenyl-dithiol junctions: Effect of electron-phonon interactions
- Univ. of Michigan, Ann Arbor, MI (United States)
The electron-phonon interaction is the dominant mechanism of inelastic scattering in molecular junctions. Here we report on its effect on the thermoelectric properties of single-molecule devices. Using density functional theory and the nonequilibrium Green’s function formalism we calculate the thermoelectric figure of merit for a biphenyl-dithiol molecule between two Al electrodes under an applied gate voltage. We find that the effect of electron-phonon coupling on the thermoelectric characteristics strongly varies with the molecular geometry. Two molecular configurations characterized by the torsion angles between the two phenyl rings of 30° and 90° exhibit significantly different responses to the inelastic scattering. We also use molecular dynamics calculations to investigate the torsional stability of the biphenyl-dithiol molecule and the phonon thermal transport in the junction.
- Research Organization:
- Energy Frontier Research Centers (EFRC) (United States). Center for Solar and Thermal Energy Conversion (CSTEC)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- DOE Contract Number:
- SC0000957
- OSTI ID:
- 1065605
- Journal Information:
- Physical Review. B, Condensed Matter and Materials Physics, Vol. 83, Issue 19; Related Information: CSTEC partners with University of Michigan (lead); Kent State University; ISSN 1098-0121
- Publisher:
- American Physical Society (APS)
- Country of Publication:
- United States
- Language:
- English
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