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Electroluminescent device with reversible switching between red and green emission
S Welter1, K Brunner, J W Hofstraat
1Molecular Photonics Group, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands.
Nature
|January 4, 2003
Summary
Researchers developed a novel organic electroluminescence device using a semiconducting polymer and a ruthenium complex. This material enables reversible switching between green and red light emission by simply changing the applied voltage.
Area of Science:
- Materials Science
- Organic Electronics
- Photophysics
Background:
- Organic electroluminescence (OEL) research prioritizes phosphorescent emitters for enhanced efficiency and stability.
- Developing novel materials is crucial for advancing OEL device performance.
Purpose of the Study:
- To fabricate a simple OEL device with voltage-dependent dual-color emission.
- To investigate a semiconducting polymer combined with a phosphorescent complex for tunable light output.
Main Methods:
- Fabrication of an OEL device using a polyphenylenevinylene (PPV) derivative doped with a dinuclear ruthenium complex.
- Utilizing the complex as both a triplet emitter and electron transfer mediator.
- Applying forward (+4 V) and reverse (-4 V) bias to control emission color.
Main Results:
- The device exhibited fully reversible voltage-dependent switching between green and red light emission.
- Forward bias resulted in red emission from the ruthenium complex.
- Reverse bias led to green emission from the polymer host via a stepwise electron transfer mechanism.
Conclusions:
- A simple OEL device demonstrating dual-color emission through voltage control was successfully fabricated.
- The dinuclear ruthenium complex plays a key role in mediating electron transfer and enabling tunable emission.
- This approach offers a promising pathway for developing advanced OEL materials with controllable light output.
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