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Updated: Feb 26, 2026
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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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Robust triplet-triplet annihilation photon upconversion by efficient oxygen scavenging
Damir Dzebo1, Kasper Moth-Poulsen, Bo Albinsson
1Chalmers University of Technology/Department of Chemistry and Chemical Engineering, 41296 Gothenburg, Sweden. balb@chalmers.se.
Summary
This study introduces a simple chemical method using thioethers to reduce oxygen quenching in Triplet-Triplet Annihilation Upconversion (TTA-UC) systems. Dimethylthiomethane (DMTM) achieved a 21% quantum yield, showing robust performance and faster setup than traditional methods.
Area of Science:
- Photochemistry
- Materials Science
- Chemical Engineering
Background:
- Oxygen quenching significantly reduces the efficiency of Triplet-Triplet Annihilation Upconversion (TTA-UC) systems.
- Traditional deoxygenation methods like gas purging or freeze-pump-thaw are time-consuming and require specialized equipment.
Purpose of the Study:
- To develop a simple and effective chemical method for reducing oxygen quenching in TTA-UC.
- To evaluate the performance of various thioethers and thiols as singlet oxygen scavengers.
- To compare the efficiency of chemical oxygen scavenging with mechanical deoxygenation techniques.
Main Methods:
- Tested commercially available thioethers and one thiol as singlet oxygen scavengers.
- Monitored upconverted emission kinetics of a PdOEP-DPA system under steady-state excitation.
- Compared TTA-UC efficiency using chemical scavenging versus inert gas purging or freeze-pump-thaw.
- Combined deoxygenation methods to maximize TTA-UC quantum yield.
Main Results:
- Dimethylthiomethane (DMTM) as a thioether scavenger yielded a maximum TTA-UC quantum yield of 21% with a short onset time.
- Chemical scavenging, especially with DMTM, proved more robust and efficient than mechanical deoxygenation.
- Samples with DMTM showed minimal quantum yield decrease over four hours of continuous irradiation.
Conclusions:
- Chemical oxygen scavenging using thioethers, particularly DMTM, offers a simple, robust, and efficient alternative to mechanical deoxygenation for TTA-UC systems.
- This method enhances TTA-UC quantum yield and stability, simplifying experimental procedures.
- The findings pave the way for more practical applications of TTA-UC technology.
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