Abstract
In the development of light-emitting materials for OLEDs, the main issue is to design light-emitting materials that can achieve a balance between high efficiency for low power consumption, color gamut expansion, and device lifetime. At present, triplet-triplet fusion methods of fluorescent emitters, phosphorescent emitters, and thermally activated delayed fluorescent emitters (TADFs) are mainly being developed as they have the potential to meet the requirements.
In this chapter, phosphorescent materials based on transition metal complexes will be discussed. The required properties for OLED emitters are reviewed, and design rules based on the luminescence mechanism of transition metal complexes are discussed. Finally, key investigations related to phosphorescent emitter materials will be reviewed, with emphasis on the most challenging blue emitting materials.
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Inoue, S., Itou, H., Kita, H. (2021). Low Molecular Weight Materials: Dry Processing. 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_6-1
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