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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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Diarylethene Isomerization by Using Triplet-Triplet Annihilation Photon Upconversion.
Wera Larsson1, Masakazu Morimoto2, Masahiro Irie2
1Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296, Göteborg, Sweden.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|December 16, 2022
Summary
Visible light drives diarylethene (DAE) photoswitch isomerization using green-to-blue photon upconversion. This method allows in situ monitoring and selective control of DAE reactions, offering an alternative to UV light.
Area of Science:
- Photochemistry
- Materials Science
- Molecular Engineering
Background:
- Triplet-triplet annihilation photon upconversion (TTA-UC) is a promising technique for visible light-driven reactions.
- Diarylethene (DAE) photoswitches are molecular systems that undergo reversible photoisomerization.
- Integrating TTA-UC with DAEs could enable new photochemical applications using visible light.
Purpose of the Study:
- To demonstrate reversible photoisomerization of DAE photoswitches using visible light via TTA-UC.
- To achieve selective control over ring-opening and ring-closing reactions of DAEs with a single light source.
- To develop an in situ monitoring method for DAE isomerization using fluorescence.
Main Methods:
- Utilized a green-to-blue TTA-UC system with 9,10-diphenylanthracene (DPA) and platinum octaethylporphyrin (PtOEP).
- Investigated the photoisomerization of DAE photoswitches driven by upconverted photons.
- Employed physically separated solutions for concomitant and individual characterization of the upconversion and DAE systems.
- Quantified the efficiency of upconverted photon-driven ring-closing reactions.
Main Results:
- Successfully drove reversible photoisomerization of DAEs using visible light through TTA-UC.
- Achieved selective triggering of both ring-opening and ring-closing reactions with a single green light source.
- Demonstrated in situ monitoring of isomerization via fluorescence from the closed DAE isomer.
- Quantified the efficiency of upconverted photon-induced isomerization, comparing it to UV-driven processes.
Conclusions:
- Visible light-driven TTA-UC provides a versatile platform for controlling DAE photoswitch isomerization.
- The developed system allows for selective reaction control and in situ monitoring without sample separation.
- Photon upconversion offers a viable alternative to UV light for DAE photoswitch applications, with potential for enhanced selectivity and safety.
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