Delocalization Drives Free Charge Generation in Conjugated Polymer Films
Abstract
We demonstrate that the product of photoinduced electron transfer between a conjugated polymer host and a dilute molecular sensitizer is controlled by the structural state of the polymer. Ordered semicrystalline solids exhibit free charge generation, while disordered polymers in the melt phase do not. We use photoluminescence (PL) and time-resolved microwave conductivity (TRMC) measurements to sweep through polymer melt transitions in situ. Free charge generation measured by TRMC turns off upon melting, whereas PL quenching of the molecular sensitizers remains constant, implying unchanged electron transfer efficiency. The key difference is the intermolecular order of the polymer host in the solid state compared to the melt. We propose that this order-disorder transition modulates the localization length of the initial charge-transfer state, which controls the probability of free charge formation.
- Authors:
-
- National Renewable Energy Lab. (NREL), Golden, CO (United States); Univ. of Colorado, Boulder, CO (United States)
- Publication Date:
- Research Org.:
- National Renewable Energy Lab. (NREL), Golden, CO (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- OSTI Identifier:
- 1426641
- Report Number(s):
- NREL/JA-5900-70921
Journal ID: ISSN 2380-8195
- Grant/Contract Number:
- AC36-08GO28308
- Resource Type:
- Accepted Manuscript
- Journal Name:
- ACS Energy Letters
- Additional Journal Information:
- Journal Volume: 3; Journal Issue: 3; Journal ID: ISSN 2380-8195
- Publisher:
- American Chemical Society (ACS)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; polymer microstructure; free charge generation; time-resolved microwave conductivity
Citation Formats
Pace, Natalie A., Reid, Obadiah G., and Rumbles, Garry. Delocalization Drives Free Charge Generation in Conjugated Polymer Films. United States: N. p., 2018.
Web. doi:10.1021/acsenergylett.8b00108.
Pace, Natalie A., Reid, Obadiah G., & Rumbles, Garry. Delocalization Drives Free Charge Generation in Conjugated Polymer Films. United States. doi:10.1021/acsenergylett.8b00108.
Pace, Natalie A., Reid, Obadiah G., and Rumbles, Garry. Mon .
"Delocalization Drives Free Charge Generation in Conjugated Polymer Films". United States. doi:10.1021/acsenergylett.8b00108. https://www.osti.gov/servlets/purl/1426641.
@article{osti_1426641,
title = {Delocalization Drives Free Charge Generation in Conjugated Polymer Films},
author = {Pace, Natalie A. and Reid, Obadiah G. and Rumbles, Garry},
abstractNote = {We demonstrate that the product of photoinduced electron transfer between a conjugated polymer host and a dilute molecular sensitizer is controlled by the structural state of the polymer. Ordered semicrystalline solids exhibit free charge generation, while disordered polymers in the melt phase do not. We use photoluminescence (PL) and time-resolved microwave conductivity (TRMC) measurements to sweep through polymer melt transitions in situ. Free charge generation measured by TRMC turns off upon melting, whereas PL quenching of the molecular sensitizers remains constant, implying unchanged electron transfer efficiency. The key difference is the intermolecular order of the polymer host in the solid state compared to the melt. We propose that this order-disorder transition modulates the localization length of the initial charge-transfer state, which controls the probability of free charge formation.},
doi = {10.1021/acsenergylett.8b00108},
journal = {ACS Energy Letters},
number = 3,
volume = 3,
place = {United States},
year = {2018},
month = {2}
}
Web of Science
Figures / Tables:

Works referencing / citing this record:
Energetics and Escape of Interchain‐Delocalized Ion Pairs in Nonpolar Media
journal, January 2019
- Burke, John H.; Bird, Matthew J.
- Advanced Materials, Vol. 31, Issue 12
What is the Binding Energy of a Charge Transfer State in an Organic Solar Cell?
journal, May 2019
- Athanasopoulos, Stavros; Schauer, Franz; Nádaždy, Vojtech
- Advanced Energy Materials, Vol. 9, Issue 24
Slow charge transfer from pentacene triplet states at the Marcus optimum
journal, November 2019
- Pace, Natalie A.; Korovina, Nadezhda V.; Clikeman, Tyler T.
- Nature Chemistry, Vol. 12, Issue 1
Figures / Tables found in this record: