Conjugated Block Copolymers as Model Systems to Examine Mechanisms of Charge Generation in Donor–Acceptor Materials
Abstract
Fully conjugated donor–acceptor block copolymers are established as model systems to elucidate fundamental mechanisms of photocurrent generation in organic photovoltaics. Using analysis of steady‐state photoluminescence quenching, exciton dissociation to a charge transfer state within individual block copolymer chains is quantified. By making a small adjustment to the conjugated backbone, the electronic properties are altered enough to disrupt charge transfer almost entirely. Strong intermolecular coupling of the electron donor is introduced by synthesizing block copolymer nanoparticles. Transient absorption spectroscopy is used to monitor charge generation in block copolymer isolated chains and nanoparticles. While efficient charge transfer is observed in isolated chains, there is no indication of complete charge separation. In the nanoparticles, long‐lived polarons are observed as early as ≈15 ns. Thus, aggregation of electron donors can facilitate efficient charge generation.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 14, 2018
- Source ID
- 10.1002/adfm.201804858
Entities
People
- Brooke Kuei
- Christopher Grieco
- Enrique Daniel Gómez
- Ismaila Dabo
- Jason M. Munro
- Jennifer L. Gray
- John B. Asbury
- Joshua H. Litofsky
- Melissa P. Aplan
- Qing Wang
- S. Michael Kilbey Ii
- Wonho Lee
- Youngmin Lee
- Zach D. Seibers
Organizations
- Office of Naval Research
- Pennsylvania State University
- United States Department of Energy
- University of Tennessee