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Title: Conjugated Block Copolymers as Model Systems to Examine Mechanisms of Charge Generation in Donor–Acceptor Materials

Journal Article · · Advanced Functional Materials
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  1. Department of Chemical Engineering The Pennsylvania State University University Park PA 16802 USA
  2. Department of Chemistry The Pennsylvania State University University Park PA 16802 USA
  3. Department of Materials Science The Pennsylvania State University University Park PA 16802 USA
  4. Materials Research Institute The Pennsylvania State University University Park PA 16802 USA
  5. Department of Chemistry University of Tennessee Knoxville TN 37996 USA
  6. Department of Chemistry University of Tennessee Knoxville TN 37996 USA, Department of Chemical and Biomolecular Engineering University of Tennessee Knoxville TN 37996 USA
  7. Department of Chemical Engineering The Pennsylvania State University University Park PA 16802 USA, Department of Materials Science The Pennsylvania State University University Park PA 16802 USA, Materials Research Institute The Pennsylvania State University University Park PA 16802 USA

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.

Sponsoring Organization:
USDOE
Grant/Contract Number:
DE‐AC02‐05CH11231
OSTI ID:
1482138
Journal Information:
Advanced Functional Materials, Journal Name: Advanced Functional Materials Vol. 29 Journal Issue: 1; ISSN 1616-301X
Publisher:
Wiley Blackwell (John Wiley & Sons)Copyright Statement
Country of Publication:
Germany
Language:
English
Citation Metrics:
Cited by: 17 works
Citation information provided by
Web of Science

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