Abstract
Curved perylene diimides fused with seven-membered rings have been synthesized using a regioselective bay-functionalization method and Pd-catalyzed intramolecular C−H/C−Br coupling reaction. X-Ray analysis and temperature-dependent NMR spectroscopy revealed the curved molecular structure with a certain degree of conformational flexibility. The curved and expanded π-conjugation altered the electronic properties while retaining the intrinsic properties of the parent perylene diimide. Despite the absence of solubilizing N-substituents, the curved perylene diimides showed sufficient solubility for application in solution-processed organic photovoltaic devices. The devices showed superior performance with a power conversion efficiency of up to 2.76% due to suppressed charge recombination. Our detailed investigations suggest that the introduction of a curved structure enables the removal of the bulky N-substituents, which is an effective way to achieve a thin-film morphology suitable for photoelectric conversion.
Original language | English |
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Pages (from-to) | 690-695 |
Number of pages | 6 |
Journal | Chemistry - An Asian Journal |
Volume | 16 |
Issue number | 6 |
DOIs | |
Publication status | Published - 15 Mar 2021 |
Keywords
- conformational flexibility
- curved π-system
- organic photovoltaics
- perylene diimide
- seven-membered ring