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Updated: May 26, 2026
11:27
Single-Molecule Förster Resonance Energy Transfer Methods for Real-Time Investigation of the Holliday Junction Resolution by GEN1
Published on: September 18, 2019
Electron transfer from singlet fission dimers: possibilities and limitations
Sree Chithra1, Corentin Pigot1, Claire Tonnelé2,3
1Department of Chemistry, Ångström Laboratory, Uppsala University Box 532 SE-751 20 Uppsala Sweden victor.gray@kemi.uu.se.
Chemical Science
|May 25, 2026
Summary
Multiexciton generation (MEG) via singlet fission (SF) can enhance photocatalysis. Researchers investigated electron transfer from SF dimers, finding challenges in achieving over 100% efficiency due to recombination.
Area of Science:
- Photocatalysis and photoredox catalysis
- Organic electronics and materials science
Background:
- Photocatalytic hydrogen or hydrocarbon production requires multiple photons and electrons.
- Multiexciton generation (MEG) offers an alternative pathway, with singlet fission (SF) being a key MEG process.
- The application of SF in photocatalysis is an emerging field, distinct from its established use in solar cells.
Purpose of the Study:
- To investigate electron transfer (ET) dynamics from tetracene-based singlet fission (SF) dimers.
- To understand the role of the singlet excited state-triplet pair (TT) and free triplet states in ET.
- To identify design principles for SF chromophores for improved solar energy conversion and photoredox catalysis.
Main Methods:
- Time-resolved spectroscopic investigation of electron transfer (ET).
- Study of covalently linked SF dimers based on tetracene.
- Theoretical calculations to complement experimental findings.
Main Results:
- The singlet excited state-triplet pair (TT) state in SF dimers exhibits singlet-like behavior, extending singlet reactivity lifetime.
- Achieving over 100% electron transfer (ET) efficiency is challenging in these dimers due to recombination pathways.
- The TT state can recombine to form a single free triplet, limiting overall charge separation.
Conclusions:
- The TT state's behavior offers opportunities to enhance singlet reactivity in photocatalysis.
- Detrimental recombination pathways of the TT state limit efficient charge separation in SF dimers.
- Strategies to mitigate recombination are crucial for designing next-generation SF chromophores for solar energy applications.
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