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Singlet exciton fission in a hexacene derivative
Jiye Lee1, Matthew J Bruzek, Nicholas J Thompson
1Energy Frontier Research Center for Excitonics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. jiye@mit.edu
Advanced Materials (Deerfield Beach, Fla.)
|January 8, 2013
Summary
Singlet fission, the conversion of one singlet exciton into two triplets, was demonstrated in hexacene derivatives. This process is facilitated by hexacene
Area of Science:
- Organic electronics
- Photophysics
- Materials science
Background:
- Acenes are organic semiconductors with potential applications in electronics.
- Hexacene, a large acene, exhibits unique electronic properties due to its extended pi-conjugation.
- Small triplet energy levels in organic molecules can enable efficient singlet fission.
Purpose of the Study:
- To demonstrate and investigate singlet fission in hexacene derivatives.
- To explore the potential of hexacene for efficient photophysical processes.
- To understand the role of molecular structure in enabling singlet fission.
Main Methods:
- Fabrication of hexacene derivative thin films.
- Transient absorption spectroscopy to monitor excited-state dynamics.
- Magnetic field effects on photocurrent to probe triplet state generation.
Main Results:
- Clear evidence of singlet fission in hexacene derivative films.
- Observation of efficient conversion of singlet excitons to triplet excitons.
- Correlation between photocurrent and triplet state population.
Conclusions:
- Hexacene derivatives are promising materials for singlet fission applications.
- Singlet fission in hexacene is efficient due to its low triplet energy.
- This work opens avenues for novel organic photovoltaic and optoelectronic devices.
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