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Low-Molecular-Weight Materials: Hole Injection Materials

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Handbook of Organic Light-Emitting Diodes

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Abstract

Low-molecular-weight hole injection materials (HIMs) are categorized as small molecules with a strong acceptor and metal oxides, and halogen derivatives. Since the relationship between the substrate work function and the ionization energy of an organic layer is important for considering the hole injection barrier, not only the HIM-dependent OLED characteristics but also the energy diagram between the anode and HIM has been extensively studied using a Kelvin probe and by ultraviolet photoelectron spectroscopy. The hole injection barrier is defined as the energy difference between the Fermi level of the anode and the highest occupied molecular orbital level of the organic layer on the anode. In this chapter, both the improvement of device characteristics using HIMs and the detailed hole injection mechanisms are summarized.

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Authors and Affiliations

  1. Science & Technology Research Laboratories, Japan Broadcasting Corporation (NHK), Tokyo, Japan

    Hirohiko Fukagawa

Authors
  1. Hirohiko Fukagawa
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Correspondence to Hirohiko Fukagawa .

Editor information

Editors and Affiliations

  1. Department of Applied Chemistry and Biochemistry, Kyushu University, Fukuoka, Japan

    Chihaya Adachi

  2. Art, Science and Technology Center for Cooperative Research, Kyushu University KASTEC, Fukuoka, Japan

    Reiji Hattori

  3. Institute for Chemical Research Division of Environmental Chemistry, Kyoto University, Kyoto, Japan

    Hironori Kaji

  4. Konica Minolta Pioneer OLED, Inc., Konica Minolta, Inc., Tokyo, Japan

    Takatoshi Tsujimura

Section Editor information

  1. Division of Environmental Chemistry, Institute for Chemical Research, Kyoto University, Kyoto, Japan

    Hironori Kaji

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Fukagawa, H. (2019). Low-Molecular-Weight Materials: Hole Injection Materials. In: Adachi, C., Hattori, R., Kaji, H., Tsujimura, T. (eds) Handbook of Organic Light-Emitting Diodes. Springer, Tokyo. https://doi.org/10.1007/978-4-431-55761-6_52-1

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  • DOI: https://doi.org/10.1007/978-4-431-55761-6_52-1

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  • Publisher Name: Springer, Tokyo

  • Print ISBN: 978-4-431-55761-6

  • Online ISBN: 978-4-431-55761-6

  • eBook Packages: Springer Reference Physics and AstronomyReference Module Physical and Materials ScienceReference Module Chemistry, Materials and Physics

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