Photo-oxidation of poly(p-phenylenevinylene)

Authors

  • Dr. Kezhao Z. Xing,

    1. Department of Physics, IFM, Linköping University S-518 83 Linköping (Sweden)
    Search for more papers by this author
  • Dr. Nicklas Johansson,

    Corresponding author
    1. Department of Physics, IFM, Linköping University S-518 83 Linköping (Sweden)
    2. Service de Chimie des Materiaux Nouveaux Centre de Recherches en Electronique et Photonique Moléculaires Université de Mons-Hainaut B-7000 Mons (Belgium)
    • Department of Physics, IFM, Linköping University S-518 83 Linköping (Sweden)
    Search for more papers by this author
  • Dr. Graham Beamson,

    1. Research Unit for Surfaces, Transforms, and Interfaces Daresbury Laboratory Warrington, Cheshire WA4 4AD (UK)
    Search for more papers by this author
  • Dr. David T. Clark,

    1. Research Unit for Surfaces, Transforms, and Interfaces Daresbury Laboratory Warrington, Cheshire WA4 4AD (UK)
    Search for more papers by this author
  • Prof. Jean-Luc Brédas,

    1. Service de Chimie des Materiaux Nouveaux Centre de Recherches en Electronique et Photonique Moléculaires Université de Mons-Hainaut B-7000 Mons (Belgium)
    Search for more papers by this author
  • Prof. William R. Salaneck

    1. Department of Physics, IFM, Linköping University S-518 83 Linköping (Sweden)
    Search for more papers by this author

  • The authors thank Prof. A. Holmes, Dr. S. Moratti, and Dr. R. W. Gymer for materials and helpful discussions, as well as Drs. M. Lögdlund, T. Kugler and B. Minaev for fruitful discussions. The work reported here was carried out with support from the European Commission ESPRIT program (project 8013, LEDFOS, which concluded at the end of 1996) and Hoechst AG, FRG. In addition, research on conjugated polymers in Linköping is supported by grants from the Swedish Natural Sciences Research Council (NFR), and the Swedish National Board for Industrial and Technical Development (NUTEK). The work in Mons is partly supported by the Belgian Federal Government Office of Science Policy, SSTC (Pǒle d'Attraction Interuniversitaire en Chimie Supramoleculaire et Catalyse), FNRS/FRFC, and an IBM Academic Joint Study. The UK, Engineering and Physical Sciences Research Council is thanked for financial support of the RUSTI Unit.

Abstract

The operating lifetime of light-emitting devices (LEDs) based on poly(p-phenylenevinylene) (PPV), one of the most widely used conjugated polymers for polymer-based LEDs, is sensitive to air exposure. The effects associated with the photo-oxidation of PPV in air are examined. Possible photo-induced oxidation products are proposed based on simulations using stilbene as a model compound. X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, and quantum-chemical calculations all indicate that a series of photo-oxidation products from on the surface of the PPV thin films.

Ancillary