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.
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Sasabe, H., Kido, J. (2019). Low Molecular Weight Materials: Electron-Transport 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_51-1
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DOI: https://doi.org/10.1007/978-4-431-55761-6_51-1
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