1
|
Musser AJ, Al-Hashimi M, Heeney M, Clark J. Heavy-atom effects on intramolecular singlet fission in a conjugated polymer. J Chem Phys 2019; 151:044902. [DOI: 10.1063/1.5110269] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- Andrew J. Musser
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
| | - Mohammed Al-Hashimi
- Department of Chemistry, Texas A&M University at Qatar, P.O. Box 23874, Doha, Qatar
| | - Martin Heeney
- Department of Chemistry and Centre for Plastic Electronics, Imperial College London, Exhibition Rd., London SW7 2AZ, United Kingdom
| | - Jenny Clark
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
| |
Collapse
|
2
|
Datko BD, Livshits MY, Zhang Z, Portlock D, Qin Y, Rack JJ, Grey JK. Unravelling the enigma of ultrafast excited state relaxation in non-emissive aggregating conjugated polymers. Phys Chem Chem Phys 2018; 20:22159-22167. [PMID: 30116824 DOI: 10.1039/c8cp04061c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We investigate a class of non-emissive conjugated polymers with very short excited state lifetimes believed to undergo singlet fission and relaxation to mid-gap forbidden excited states. Poly(3-decylthieneylenvinylene) (P3DTV) and its heavy atom analog, poly(3-decylseleneylenvinylene) (P3DSV), are strongly aggregating conjugated polymers that experience large excited state displacements along multiple vibrational modes. We demonstrate this Franck-Condon vibrational activity effectively disperses excitation energy into multiple non-radiative channels that can be explained using a simple, two-state potential energy surface model. Resonance Raman spectroscopy is sensitive to early Franck-Condon vibrational activity and we observe rich harmonic progressions involving multiple high frequency CC backbone symmetric stretching motions (∼1000-1600 cm-1) in both systems reflecting mode-specific excited state geometrical displacements. Transient absorption spectra confirm that efficient non-radiative processes dominate excited state relaxation dynamics which are confined to π-stacked aggregated chains. Surprisingly, we found little influence of the heteroatom consistent with efficient vibrational energy dissipation. Our results highlight the importance of aggregation and multi-dimensional Franck-Condon vibrational dynamics on the ability to harvest excitons, which are not usually considered in materials design and optimization schemes.
Collapse
Affiliation(s)
- Benjamin D Datko
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM 87131, USA.
| | | | | | | | | | | | | |
Collapse
|
3
|
Musser AJ, Al-Hashimi M, Maiuri M, Brida D, Heeney M, Cerullo G, Friend RH, Clark J. Activated singlet exciton fission in a semiconducting polymer. J Am Chem Soc 2013; 135:12747-54. [PMID: 23883167 DOI: 10.1021/ja405427j] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Singlet exciton fission is a spin-allowed process to generate two triplet excitons from a single absorbed photon. This phenomenon offers great potential in organic photovoltaics, but the mechanism remains poorly understood. Most reports to date have addressed intermolecular fission within small-molecular crystals. However, through appropriate chemical design chromophores capable of intramolecular fission can also be produced. Here we directly observe sub-100 fs activated singlet fission in a semiconducting poly(thienylenevinylene). We demonstrate that fission proceeds directly from the initial 1Bu exciton, contrary to current models that involve the lower-lying 2Ag exciton. In solution, the generated triplet pairs rapidly recombine and decay through the 2Ag state. In films, exciton diffusion breaks this symmetry and we observe long-lived triplets which form charge-transfer states in photovoltaic blends.
Collapse
Affiliation(s)
- Andrew J Musser
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom.
| | | | | | | | | | | | | | | |
Collapse
|
4
|
Apperloo JJ, Martineau C, van Hal PA, Roncali J, Janssen RAJ. Intra- and Intermolecular Photoinduced Energy and Electron Transfer between Oligothienylenevinylenes and N-Methylfulleropyrrolidine. J Phys Chem A 2001. [DOI: 10.1021/jp012936f] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joke J. Apperloo
- Laboratory for Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, and Ingénierie Moléculaire et Matériaux Organiques, CNRS UMR 6501, Université d'Angers, 2 Boulevard Lavoisier, F-49045 Angers Cedex, France
| | - Corinne Martineau
- Laboratory for Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, and Ingénierie Moléculaire et Matériaux Organiques, CNRS UMR 6501, Université d'Angers, 2 Boulevard Lavoisier, F-49045 Angers Cedex, France
| | - Paul A. van Hal
- Laboratory for Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, and Ingénierie Moléculaire et Matériaux Organiques, CNRS UMR 6501, Université d'Angers, 2 Boulevard Lavoisier, F-49045 Angers Cedex, France
| | - Jean Roncali
- Laboratory for Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, and Ingénierie Moléculaire et Matériaux Organiques, CNRS UMR 6501, Université d'Angers, 2 Boulevard Lavoisier, F-49045 Angers Cedex, France
| | - René A. J. Janssen
- Laboratory for Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, and Ingénierie Moléculaire et Matériaux Organiques, CNRS UMR 6501, Université d'Angers, 2 Boulevard Lavoisier, F-49045 Angers Cedex, France
| |
Collapse
|