Blue phosphorescent iridium(iii) complexes containing carbazole-functionalized phenylpyridine for organic light-emitting diodes: energy transfer from carbazolyl moieties to iridium(iii) cores

By introducing a hexylcarbazolyl substituent into a phenylpyridine-based ligand, a Forster energy transfer from the carbazole moieties to the Ir(iii) cores was observed in the heteroleptic cyclometalated Ir(iii) complexes, resulting in an enhancement of luminescent efficiency. The phosphorescent OLED gave CIE coordinates of (0.21, 0.55) with a maximum external quantum efficiency of 7.16%.