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Decoupling Charge Transport and Electroluminescence in a High Mobility Polymer Semiconductor
David J Harkin1, Katharina Broch1, Maximilian Schreck2
1Department of Physics, University of Cambridge, Cambridge, CB3 0HE, UK.
Advanced Materials (Deerfield Beach, Fla.)
|May 12, 2016
Summary
High-mobility polymer semiconductors show enhanced fluorescence through energy transfer to squaraine dyes. This boosts organic light-emitting diode efficiency by tenfold without sacrificing charge-carrier mobility.
Area of Science:
- Organic electronics
- Photophysics
- Materials science
Background:
- Polymer semiconductors are crucial for organic electronics but often suffer from low fluorescence.
- Improving fluorescence quantum yield is key to enhancing device performance.
Purpose of the Study:
- To achieve fluorescence enhancement in high-mobility polymer semiconductors.
- To investigate energy transfer mechanisms for improved light emission.
Main Methods:
- Utilized energy transfer from a polymer semiconductor to a squaraine dye molecule.
- Investigated processes on picosecond (ps) timescales.
- Fabricated and tested organic light-emitting diodes (OLEDs).
Main Results:
- Achieved fluorescence enhancement via energy transfer.
- Observed an order of magnitude increase in external quantum efficiency in OLEDs.
- Maintained charge-carrier mobility.
- Reached radiances up to 5 W str(-1) m(-2) at 800 nm.
Conclusions:
- Energy transfer to higher quantum yield squaraine dyes effectively enhances polymer semiconductor fluorescence.
- This method offers a pathway to highly efficient OLEDs with maintained charge transport properties.
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