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Updated: Jun 28, 2026
05:51
Fabrication of White Light-emitting Electrochemical Cells with Stable Emission from Exciplexes
Published on: November 15, 2016
A supramolecularly-caged ionic iridium(III) complex yielding bright and very stable solid-state light-emitting
Stefan Graber1, Kevin Doyle, Markus Neuburger
1Department of Chemistry, University of Basel, Spitalstrasse 51, CH-4056 Basel, Switzerland.
Journal of the American Chemical Society
|October 22, 2008
Summary
A novel iridium(III) complex with pi-stacking enhances the stability of solid-state light-emitting electrochemical cells (LECs). This breakthrough offers a path toward practical applications with extended device lifetimes and high luminance.
Area of Science:
- Materials Science
- Chemistry
- Solid-State Physics
Background:
- Light-emitting electrochemical cells (LECs) are promising for lighting applications.
- Improving the operational stability and luminance of LECs is crucial for practical use.
- Existing ionic complexes often lack the required long-term stability.
Purpose of the Study:
- To synthesize a new iridium(III) complex with intramolecular interligand pi-stacking.
- To investigate the impact of this complex on the stability of single-component, solid-state LEC devices.
- To assess the potential of this approach for achieving practical LEC applications.
Main Methods:
- Synthesis of a novel iridium(III) complex featuring intramolecular interligand pi-stacking.
- Fabrication of single-component, solid-state light-emitting electrochemical cell (LEC) devices utilizing the synthesized complex.
- Characterization of the device performance, including stability (lifetime) and luminance measurements.
Main Results:
- A stable supramolecularly caged iridium(III) complex was formed due to pi-stacking.
- LECs incorporating this complex demonstrated extraordinary stability, with an estimated lifetime of 600 hours.
- The devices achieved high average luminance values of 230 cd m-2.
Conclusions:
- Intramolecular interligand pi-stacking in iridium(III) complexes can significantly enhance LEC stability.
- The developed complex offers a viable route towards highly stable and efficient solid-state LECs.
- This research paves the way for practical applications of LEC technology.
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