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DOE OSTI · 1650832

Molecular compositions, materials, and methods for efficient multiple exciton generation

Abstract

Embodiments of the present invention provides compounds, compositions, and methods for their preparation that provide efficient intramolecular fission, such that local order and strong nearest neighbor coupling is no longer a design constraint. Inventive materials include organic oligomers and polymers designed to exhibit strong intrachain donor-acceptor interactions and provide intramolecular singlet fission, whereby triplet populations can be generated in very high yields of, e.g., 170% or more. The inventive disclosure is directed to polymers of the general formula: [SA-SD]n with a strong electron acceptor (SA), a strong electron donor (SD), and n a positive integer equal to or greater than two; methods for their preparation and monomers used therein, blends, mixtures and formulations containing them; the use of the polymers, blends, mixtures and formulations as semiconductors in organic electronic (OE) devices, especially in organic photovoltaic (OPV) devices, and to OE and OPV devices comprising these polymers, blends, mixtures or formulations.

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BibTeXRIS

Campos, Luis M., Sfeir, Matthew Y., Xia, Jianlong, Busby, Erik Michael Allan, Low, Jonathan Zhaozhi. 2020-04-28. Molecular compositions, materials, and methods for efficient multiple exciton generation. https://www.osti.gov/biblio/1650832

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36 MATERIALS SCIENCE↗