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Low Molecular Weight Materials: Electron-Transport Materials

  • Hisahiro SasabeEmail author
  • Junji Kido
Living reference work entry

Abstract

Since the first report of practical OLED by Tang and VanSlyke in 1987, metal complex, 8-hydroxyquinoline aluminum (Alq) is widely used for fluorescent OLEDs. However, Alq cannot be used in second- and third-generation green and blue OLEDs due to its low triplet energy (ET) of 2.15 eV. Therefore, researchers have been exploring a novel ETM with high ET in this decade. In this chapter, we summarized and demonstrated representative wide-energy-gap ETMs for use in second- and third-generation OLEDs, and some typical strategies for high-performance ETMs are demonstrated. Further, future challenges are briefly discussed.

Keywords

Electron-transport material Wide-energy gap Low-operating-voltage Electron mobility Molecular orientation Weak hydrogen bond 

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Copyright information

© Springer Japan KK, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Organic Device EngineeringYamagata UniversityYonezawaJapan
  2. 2.Graduate School of Organic Materials Science, Research Center for Organic ElectronicsYamagata UniversityYamagataJapan

Section editors and affiliations

  • Hironori Kaji
    • 1
  1. 1.Division of Environmental Chemistry, Institute for Chemical ResearchKyoto UniversityKyotoJapan

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