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Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light
Published on: September 12, 2014
Tetracene Dimers: A Platform for Intramolecular Down- and Up-conversion.
Yifan Bo1, Yuxuan Hou2, Dominik Thiel1
1Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany.
Researchers explored how tetracene dimers can convert photon energy using singlet fission (SF) and triplet-triplet annihilation up-conversion (TTA-UC). They characterized the interplay between these processes and the impact of temperature on their efficiency.
Area of Science:
- Materials Science
- Photochemistry
- Renewable Energy
Background:
- Photon energy conversion is crucial for solar cell efficiency.
- Singlet fission (SF) and triplet-triplet annihilation up-conversion (TTA-UC) are two key processes.
- Tetracene exhibits potential for both SF and TTA-UC.
Purpose of the Study:
- To design and characterize tetracene dimers with varying electronic coupling.
- To investigate the interplay between intramolecular SF and TTA-UC.
- To explore indirect photoexcitation of TTA-UC and temperature effects.
Main Methods:
- Synthesis of meta-diethynylphenylene- and 1,3-diethynyladamantyl-linked tetracene dimers.
- Steady-state and time-resolved absorption and fluorescence spectroscopy.
- Temperature-dependent measurements and indirect photoexcitation using Pd-phthalocyanine.
Main Results:
- Designed tetracene dimers with distinct electronic coupling for studying intra-SF and intra-TTA-UC.
- Characterized the interplay between intramolecular SF and TTA-UC processes.
- Demonstrated indirect photoexcitation of intra-TTA-UC and analyzed thermal effects.
Conclusions:
- Tetracene dimers offer a platform to study competing photon energy conversion pathways.
- Understanding the interplay of SF and TTA-UC is vital for optimizing solar energy harvesting.
- Temperature significantly influences the efficiency of these intramolecular processes.
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