Title
Signatures of intracrystallite and intercrystallite limitations of charge transport in polythiophenes
Date Issued
11 October 2016
Access level
metadata only access
Resource Type
journal article
Author(s)
Vakhshouri K.
Smith B.
Chan E.
Wang C.
Salleo A.
Wang C.
Hexemer A.
University Park
Publisher(s)
American Chemical Society
Abstract
Charge carrier mobilities in conjugated semicrystalline polymers depend on morphological parameters such as crystallinity, crystal orientation, and connectivity between ordered regions. Despite recent progress in the development of conducting polymers, the complex interplay between the aforementioned parameters and their impact on charge transport is not fully understood. By varying the casting solvents and thermal annealing, we have systematically modulated the crystallization of poly(3-hexylthiophene-2,5-diyl) (P3HT) and poly[2,5-bis(3-hexadecylthiophen-2-yl)thieno(3,2-b)thiophene] (PBTTT) thin films to examine the role of microstructure on charge mobilities. In particular, we achieve equal crystallinities through different processing routes to examine the role of structural parameters beyond the crystallinity on charge mobilities. As expected, a universal relationship does not exist between the crystallinity in either P3HT and PBTTT active layers and the charge mobility in devices. In P3HT films, higher boiling point solvents yield longer conjugation lengths, an indicator of stronger intracrystalline order, and therefore higher device mobilities. In contrast, the charge mobilities of PBTTT devices depend on the interconnectivity between crystallites and intercrystalline order in the active layer.
Start page
7359
End page
7369
Volume
49
Issue
19
Language
English
OCDE Knowledge area
Ciencia de los polímeros Ingeniería química
Scopus EID
2-s2.0-84991384239
Source
Macromolecules
ISSN of the container
00249297
Sponsor(s)
Duc T. Duong is gratefully acknowledged for assistance in analyzing absorption spectra. Major funding for this work was provided by the Center for Flexible Electronics at Penn State sponsored by The Dow Chemical Company and NSF under Grant DMR-1056199. The authors also acknowledge the support of the Advanced Light Source, Lawrence Berkeley National Laboratory, which is supported by the U.S. Department of Energy under Contract DE-AC02-05CH11231.
Sources of information: Directorio de Producción Científica Scopus