Increasing the Thermoelectric Power Factor of a Semiconducting Polymer by Doping from the Vapor Phase
Journal article, 2016

We demonstrate how processing methods affect the thermoelectric properties of thin films of a high mobility semiconducting polymer, PBTTT. Two doping methods were compared: vapor deposition of (tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane (FTS) or immersion in a solvent containing 4-ethylbenzenesulfonic acid (EBSA). Thermally annealed, thin films doped by FTS deposited from vapor yield a high Seebeck coefficient (α) at high electronic conductivity (σ) and, in turn, a large power factor (PF = α2σ) of ∼100 μW m–1 K–2. The FTS-doped films yield α values that are a factor of 2 higher than the EBSA-doped films at comparable high value of σ. A detailed analysis of X-ray scattering experiments indicates that perturbations in the local structure from either dopant are not significant enough to account for the difference in α. Therefore, we postulate that an increase in α arises from the entropic vibrational component of α or changes in scattering of carriers in disordered regions in the film.

doping

thermoelectric power factor

PBTTT

vapor phase

EBSA

FTS

Author

Shrayesh N. Patel

University of California

Anne M. Glaudell

University of California

David Kiefer

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Polymer Technology

Michael L. Chabinyc

University of California

ACS Macro Letters

2161-1653 (eISSN)

Vol. 5 3 268-272

Subject Categories

Polymer Chemistry

Materials Chemistry

Condensed Matter Physics

Areas of Advance

Materials Science

DOI

10.1021/acsmacrolett.5b00887

More information

Latest update

2/28/2018