Synthesis and Photophysical Properties of Charged Iridium(III) Cyclometallates Based on Hole-Transporting Carbazole Unit

Abstract:

Four novel charged Ir (III) cyclometallates based on 9-phenylcarbazole unit have been developed. By attaching isoquinoline or 5-trifluoromethylpyridine group, the light-emitting properties of the resulting Ir (III) cyclometallates have been improved. Meanwhile, 1,10-phenanthroline or 4,4′-dimethyl-2,2′-bipyridine has been utilized to modify the thermal stability. The four Ir (III) cyclometallates emit yellow light with the highest photoluminescence quantum yields (Φ_P) of 0.32 (C4), which is only less than that of the state-of-art complex fac-tris (2-phenylpyridine) iridium (III) [fac-Ir (ppy)₃], which shows Φ_P of 0.40 under the same condition. This inspiring result reveals that the bulky character of CF₃ group enhances the performance of reported charged Ir (III) cyclometallates and makes them to be potential phosphors in OLED applications.

• Periodical: Applied Mechanics and Materials (Volumes 633-634)
• Pages: 314-319
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.633-634.314
• Online since: September 2014
• Authors: Gui Ping Tan*, Hong Bo Fan, Wai Yeung Wong
• Keywords: Carbazole, Charged Iridium (III) Cyclometallates, Hole-Transporting

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