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Interactive radical dimers in photoconductive organic thin films
Akito Iwasaki1, Laigui Hu, Rie Suizu
1Research Center for Materials Science and Department of Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan.
Angewandte Chemie (International Ed. in English)
|April 28, 2009
Summary
Radical dimers with overlapping molecular orbitals show high photoconductivity. These materials, used in sandwich-type cells, demonstrate efficient photocurrent generation and photovoltaic effects.
Area of Science:
- Materials Science
- Organic Electronics
- Photoconductivity
Background:
- Organic radical dimers are promising materials for electronic applications.
- Understanding the relationship between molecular orbital overlap and photoconductivity is crucial for device optimization.
Purpose of the Study:
- To investigate the photoconductivity of interactive radical dimers.
- To explore the role of extended unoccupied molecular orbital overlap in device performance.
Main Methods:
- Fabrication of sandwich-type cells using highly oriented thin films of 4,4'-bis(1,2,3,5-dithiadiazolyl) (BDTDA).
- Measurement of photocurrent under varying bias voltages.
- Characterization of photovoltaic behavior.
Main Results:
- The radical dimers exhibit high photoconductivity.
- A high photocurrent on/off ratio was observed at reverse bias voltages.
- Photovoltaic behavior was demonstrated at zero bias voltage.
Conclusions:
- Overlap between extended unoccupied molecular orbitals is key to high photoconductivity in these radical dimers.
- BDTDA-based cells show potential for efficient optoelectronic devices.
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