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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
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Doublet-Triplet Energy Transfer-Dominated Photon Upconversion.
Jianlei Han1, Yuqian Jiang1, Ablikim Obolda2
1Division of Nanophotonics, CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology (NCNST) , No. 11 ZhongGuanCun BeiYiTiao, 100190 Beijing, People's Republic of China.
The Journal of Physical Chemistry Letters
|November 17, 2017
Summary
Stable luminescent pi-radicals are promising for molecular materials. We developed a new pi-radical dye, TTM-1Cz, enabling efficient red-to-blue light upconversion via doublet-triplet energy transfer for photon upconversion applications.
Area of Science:
- Materials Science
- Photochemistry
- Organic Chemistry
Background:
- Stable luminescent pi-radicals with doublet emission are of increasing interest for advanced molecular materials.
- Photon upconversion technologies are crucial for applications requiring light wavelength conversion.
Purpose of the Study:
- To demonstrate a novel neutral pi-radical dye, TTM-1Cz, as an efficient triplet sensitizer for photon upconversion.
- To investigate the underlying photophysical mechanisms, specifically doublet-triplet energy transfer (DTET).
Main Methods:
- Synthesis and characterization of the neutral pi-radical dye TTM-1Cz.
- Photophysical studies including absorption, emission, and lifetime measurements.
- Theoretical calculations to confirm the Dexter-like excited doublet-triplet energy transfer (DTET) mechanism.
Main Results:
- TTM-1Cz exhibits remarkable doublet emission and functions as an effective triplet sensitizer.
- Red light (635 nm) was successfully upconverted to blue or cyan light using TTM-1Cz and aromatic emitters.
- An anti-Stokes energy shift of 0.92 eV was achieved, demonstrating efficient energy transfer.
Conclusions:
- The developed pi-radical dye TTM-1Cz is a novel and effective triplet sensitizer for triplet-triplet annihilation photon upconversion (TTA-UC).
- The discovery of DTET phenomena provides a new pathway for designing efficient sensitizers in TTA-UC systems.
- This work opens avenues for new functional molecular materials with tailored optical properties.
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