Single molecule spectroscopy of red- and green-emitting fluorene-based copolymers

Khalil, G. E.; Adawi, A. M.; Fox, A. M.; Iraqi, A.; Lidzey, D. G.

Abstract

Single molecule fluorescence spectroscopy is used to study the optical properties of two polymers: a fluorene-based statistical copolymer that contains a low fraction (10%) of a red-emitting thiophene group, and the green-emitting polymer poly(9,9-dioctylfluorene-alt-benzothiadiazole). These polymers were studied when isolated at a low concentration in a polymer matrix (either polynorbornene or polystyrene). For the red-emitting polymer, we compare the relative emission intensity from the green-emitting benzothiadiazole groups with the red-emitting thiophene. We find that red emission from the thiophenes is significantly suppressed in the single molecule regime, suggesting that interchain energy transfer dominates intrachain processes in such polyfluorene copolymers. We then use fluorescence spectroscopy and polarization anisotropy measurements to show that the conformations of both polymers are dependent on their host matrix, adopting a more collapsed, globular conformation in polystyrene and a more extended chain conformation in polynorbornene.

Citation

Khalil, G. E., Adawi, A. M., Fox, A. M., Iraqi, A., & Lidzey, D. G. (2009). Single molecule spectroscopy of red- and green-emitting fluorene-based copolymers. The Journal of chemical physics, 130(4), 044903. https://doi.org/10.1063/1.3054142

• Journal Article Type: Article
• Acceptance Date: Dec 1, 2008
• Online Publication Date: Jan 26, 2009
• Publication Date: Feb 9, 2009
• Journal: JOURNAL OF CHEMICAL PHYSICS
• Print ISSN: 0021-9606
• Publisher: American Institute of Physics
• Peer Reviewed: Peer Reviewed
• Volume: 130
• Issue: 4
• Article Number: ARTN 044903
• Pages: 044903
• DOI: https://doi.org/10.1063/1.3054142
• Keywords: Physical and Theoretical Chemistry; General Physics and Astronomy
• Public URL: https://hull-repository.worktribe.com/output/400139