Electroluminescence in conjugated polymers

Abstract

Research in the use of organic polymers as the active semiconductors in light-emitting diodes has advanced rapidly, and prototype devices now meet realistic specifications for applications. These achievements have provided insight into many aspects of the background science, from design and synthesis of materials, through materials fabrication issues, to the semiconductor physics of these polymers.

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Figure 1: Structures of some molecular semiconductors that have been used in thin-film electroluminescent devices.
Figure 2: Polymers used in electroluminescent diodes.
Figure 3: Structure and schematic energy-level diagram of a single-layer polymer electroluminescent diode.
Figure 4: Photoluminescence spectra from PPV.
Figure 5: Current density and light output versus drive voltage for green-emitting polymer LEDs based on polyfluorene26.
Figure 6: Energy levels for electroluminescent diodes.
Figure 7: Schematic representation of pathways for singlet decay as well as triplet excitation and decay.

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Acknowledgements

We thank the European Commission (ESPRIT programme 8013 LEDFOS) for support. Research in Mons is partly supported by the Belgian Federal Government (Pôle d'Attraction Interuniversitaire en Chimie Supramoléculaire et Catalyse), FRNS-FRFC, and an IBM Academic Joint Study.

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Friend, R., Gymer, R., Holmes, A. et al. Electroluminescence in conjugated polymers. Nature 397, 121–128 (1999). https://doi.org/10.1038/16393

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