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Population dynamics of multiple triplet excitons revealed from time-dependent fluorescence quenching of single conjugated polymer chains
The advent of multiple exciton harvesting schemes and prolonging exciton lifetimes to improve performance attributes of solar cells based on conjugated organic materials presents some interesting challenges that must be overcome in order to realize the full potential of these strategies. This is esp...
Autores principales: | , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Nature Publishing Group UK
2019
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6349865/ https://www.ncbi.nlm.nih.gov/pubmed/30692627 http://dx.doi.org/10.1038/s41598-018-37477-8 |
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author | Datko, Benjamin D. Grey, John K. |
author_facet | Datko, Benjamin D. Grey, John K. |
author_sort | Datko, Benjamin D. |
collection | PubMed |
description | The advent of multiple exciton harvesting schemes and prolonging exciton lifetimes to improve performance attributes of solar cells based on conjugated organic materials presents some interesting challenges that must be overcome in order to realize the full potential of these strategies. This is especially important for applications involving multi-chromophoric conjugated polymers where interactions between multiple spin-forbidden triplet excitons can be significant and are mediated by chain conformation. We use single molecule spectroscopic techniques to investigate interactions between multiple triplet excitons and emissive singlets by monitoring time-dependent fluorescence quenching on time scales commensurate with the triplet lifetime. Structurally related conjugated polymers differing by heteroatom substitution were targeted and we use a stochastic photodynamic model to numerically simulate the evolution of multi-exciton populations following photoexcitation. Single chains of poly(3-hexylthiophene) (P3HT) exhibit longer-lived triplet dynamics and larger steady-state triplet occupancies compared to those of poly(3-hexylselenophene) (P3HS), which has a larger reported triplet yield. Triplet populations evolve and relax much faster in P3HS which only becomes evident when considering all kinetic factors governing exciton population dynamics. Overall, we uncover new guidelines for effectively managing multi-exciton populations and interactions in conjugated polymers and improving their light harvesting efficiency. |
format | Online Article Text |
id | pubmed-6349865 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | Nature Publishing Group UK |
record_format | MEDLINE/PubMed |
spelling | pubmed-63498652019-01-30 Population dynamics of multiple triplet excitons revealed from time-dependent fluorescence quenching of single conjugated polymer chains Datko, Benjamin D. Grey, John K. Sci Rep Article The advent of multiple exciton harvesting schemes and prolonging exciton lifetimes to improve performance attributes of solar cells based on conjugated organic materials presents some interesting challenges that must be overcome in order to realize the full potential of these strategies. This is especially important for applications involving multi-chromophoric conjugated polymers where interactions between multiple spin-forbidden triplet excitons can be significant and are mediated by chain conformation. We use single molecule spectroscopic techniques to investigate interactions between multiple triplet excitons and emissive singlets by monitoring time-dependent fluorescence quenching on time scales commensurate with the triplet lifetime. Structurally related conjugated polymers differing by heteroatom substitution were targeted and we use a stochastic photodynamic model to numerically simulate the evolution of multi-exciton populations following photoexcitation. Single chains of poly(3-hexylthiophene) (P3HT) exhibit longer-lived triplet dynamics and larger steady-state triplet occupancies compared to those of poly(3-hexylselenophene) (P3HS), which has a larger reported triplet yield. Triplet populations evolve and relax much faster in P3HS which only becomes evident when considering all kinetic factors governing exciton population dynamics. Overall, we uncover new guidelines for effectively managing multi-exciton populations and interactions in conjugated polymers and improving their light harvesting efficiency. Nature Publishing Group UK 2019-01-28 /pmc/articles/PMC6349865/ /pubmed/30692627 http://dx.doi.org/10.1038/s41598-018-37477-8 Text en © The Author(s) 2019 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. |
spellingShingle | Article Datko, Benjamin D. Grey, John K. Population dynamics of multiple triplet excitons revealed from time-dependent fluorescence quenching of single conjugated polymer chains |
title | Population dynamics of multiple triplet excitons revealed from time-dependent fluorescence quenching of single conjugated polymer chains |
title_full | Population dynamics of multiple triplet excitons revealed from time-dependent fluorescence quenching of single conjugated polymer chains |
title_fullStr | Population dynamics of multiple triplet excitons revealed from time-dependent fluorescence quenching of single conjugated polymer chains |
title_full_unstemmed | Population dynamics of multiple triplet excitons revealed from time-dependent fluorescence quenching of single conjugated polymer chains |
title_short | Population dynamics of multiple triplet excitons revealed from time-dependent fluorescence quenching of single conjugated polymer chains |
title_sort | population dynamics of multiple triplet excitons revealed from time-dependent fluorescence quenching of single conjugated polymer chains |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6349865/ https://www.ncbi.nlm.nih.gov/pubmed/30692627 http://dx.doi.org/10.1038/s41598-018-37477-8 |
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