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Enhanced Thermoelectric Power Factor of Tensile Drawn Poly(3-hexylthiophene).

ABSTRACT: The thermoelectric power factor of a broad range of organic semiconductors scales with their electrical conductivity according to a widely obeyed power law, and therefore, strategies that permit this empirical trend to be surpassed are highly sought after. Here, tensile drawing of the conjugated polymer poly(3-hexylthiophene) (P3HT) is employed to create free-standing films with a high degree of uniaxial alignment. Along the direction of orientation, sequential doping with a molybdenum tris(dithiolene) complex leads to a 5-fold enhancement of the power factor beyond the predicted value, reaching up to 16 ?W m-1 K-2 for a conductivity of about 13 S cm-1. Neither stretching nor doping affect the glass transition temperature of P3HT, giving rise to robust free-standing materials that are of interest for the design of flexible thermoelectric devices.

SUBMITTER: Hynynen J

PROVIDER: S-EPMC6344060 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Enhanced Thermoelectric Power Factor of Tensile Drawn Poly(3-hexylthiophene).

Hynynen Jonna J Järsvall Emmy E Kroon Renee R Zhang Yadong Y Barlow Stephen S Marder Seth R SR Kemerink Martijn M Lund Anja A Müller Christian C

ACS macro letters 20181226 1

The thermoelectric power factor of a broad range of organic semiconductors scales with their electrical conductivity according to a widely obeyed power law, and therefore, strategies that permit this empirical trend to be surpassed are highly sought after. Here, tensile drawing of the conjugated polymer poly(3-hexylthiophene) (P3HT) is employed to create free-standing films with a high degree of uniaxial alignment. Along the direction of orientation, sequential doping with a molybdenum tris(dith ...[more]

PMID: 30701126

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