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Thermoelectric Properties of 2,7-Dipyridylfluorene Derivatives in Single-Molecule Junctions.

ABSTRACT: A series of 2,7-dipyridylfluorene derivatives have been synthesized with different substituents (2H, 2Me, 2OMe, 2CF₃, and O) at the C(9) position. Experimental measurements on gold|single-molecule|gold junctions, using a modified scanning tunneling microscope-break-junction technique, show that the C(9) substituent has little effect on the conductance, although there is a more significant influence on the thermopower, with the Seebeck coefficient varying by a factor of 1.65 within the series. The combined experimental and computational study, using density functional theory calculations, provides insights into the interplay of conductance and thermopower in single-molecule junctions and is a guide for new strategies for thermopower modulation in single-molecule junctions.

SUBMITTER: Yzambart G

PROVIDER: S-EPMC6503582 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Thermoelectric Properties of 2,7-Dipyridylfluorene Derivatives in Single-Molecule Junctions.

Yzambart Gilles G Rincón-García Laura L Al-Jobory Alaa A AA Ismael Ali K AK Rubio-Bollinger Gabino G Lambert Colin J CJ Agraït Nicolás N Bryce Martin R MR

The journal of physical chemistry. C, Nanomaterials and interfaces 20181121 48

A series of 2,7-dipyridylfluorene derivatives have been synthesized with different substituents (2H, 2Me, 2OMe, 2CF<sub>3</sub>, and O) at the C(9) position. Experimental measurements on gold|single-molecule|gold junctions, using a modified scanning tunneling microscope-break-junction technique, show that the C(9) substituent has little effect on the conductance, although there is a more significant influence on the thermopower, with the Seebeck coefficient varying by a factor of 1.65 within the ...[more]

PMID: 31080539

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