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Self-Sensitized Photooxidation in Extended Tetrathiafulvalenes
Alexander L O Degner1,2, Amanda F Smith1,2, Duccio Di Prima1
1Department of Physics, Chemistry, and Pharmacy, University of Southern Denmark, Odense 5230, Denmark.
The Journal of Organic Chemistry
|April 6, 2026
Summary
Novel organic dyes based on 2,1,3-benzothiadiazole extended tetrathiafulvalenes were synthesized. These dyes show improved photostability by reducing singlet oxygen generation, crucial for organic photovoltaics applications.
Area of Science:
- Materials Science
- Organic Chemistry
- Photovoltaics
Background:
- Photostability of organic dyes is crucial for organic photovoltaics (OPVs) performance.
- Degradation under light and air exposure limits the efficiency and lifespan of OPVs.
- Extended tetrathiafulvalenes are promising dye candidates for OPVs.
Purpose of the Study:
- To synthesize novel 2,1,3-benzothiadiazole-based extended tetrathiafulvalenes.
- To investigate the photophysical properties of these novel compounds.
- To clarify the role of dithiafulvene units in singlet molecular oxygen sensitization.
Main Methods:
- Synthesis of novel 2,1,3-benzothiadiazole-based extended tetrathiafulvalenes.
- Photophysical characterization of the synthesized compounds.
- Analysis of singlet molecular oxygen generation and degradation pathways.
Main Results:
- Successful synthesis of a series of novel 2,1,3-benzothiadiazole-based extended tetrathiafulvalenes.
- Photophysical analyses revealed a correlation between dithiafulvene units and reduced singlet oxygen generation.
- The presence of dithiafulvene units leads to [2 + 2] cycloaddition reactions and subsequent cleavage.
Conclusions:
- The synthesized extended tetrathiafulvalenes exhibit tunable photophysical properties.
- Dithiafulvene units play a significant role in mitigating singlet oxygen sensitization, enhancing dye photostability.
- These findings contribute to the development of more stable organic dyes for organic photovoltaics.
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