Driving Force and Optical Signatures of Bipolaron Formation in Chemically Doped Conjugated Polymers

Bibliographische Detailangaben
Veröffentlicht in:	Advanced materials (Deerfield Beach, Fla.). - 1998. - 33(2021), 3 vom: 24. Jan., Seite e2000228
1. Verfasser:	Voss, Matthew G (VerfasserIn)
Weitere Verfasser:	Challa, J Reddy, Scholes, D Tyler, Yee, Patrick Y, Wu, Eric C, Liu, Xiao, Park, Sanghyun J, León Ruiz, Omar, Subramaniyan, Selvam, Chen, Mengdan, Jenekhe, Samson A, Wang, Xiaolin, Tolbert, Sarah H, Schwartz, Benjamin J
Format:	Online-Aufsatz
Sprache:	English
Veröffentlicht:	2021
Zugriff auf das übergeordnete Werk:	Advanced materials (Deerfield Beach, Fla.)
Schlagworte:	Journal Article bipolarons donor-acceptor copolymers molecular dopants semiconducting polymers transient absorption spectroscopy

Beschreibung
Zusammenfassung:	© 2020 Wiley-VCH GmbH. Molecular dopants are often added to semiconducting polymers to improve electrical conductivity. However, the use of such dopants does not always produce mobile charge carriers. In this work, ultrafast spectroscopy is used to explore the nature of the carriers created following doping of conjugated push-pull polymers with both F4 TCNQ (2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane) and FeCl3 . It is shown that for one particular push-pull material, the charge carriers created by doping are entirely non-conductive bipolarons and not single polarons, and that transient absorption spectroscopy following excitation in the infrared can readily distinguish the two types of charge carriers. Based on density functional theory calculations and experiments on multiple push-pull conjugated polymers, it is argued that the size of the donor push units determines the relative stabilities of polarons and bipolarons, with larger donor units stabilizing the bipolarons by providing more area for two charges to co-reside
Beschreibung:	Date Revised 22.02.2021 published: Print-Electronic Citation Status PubMed-not-MEDLINE
ISSN:	1521-4095
DOI:	10.1002/adma.202000228