Carbazole and arylamine functionalized iridium complexes for efficient electro-phosphorescent light-emitting diodes

We report the synthesis and characterization of four cyclometalated iridium complexes based on carbazole and arylamine modified 2-phenylpyridine. The carbazole and arylamine groups are linked to 2-phenyl pyridine backbone to enhance the energy harvesting and transfer from host to guest materials. The electrochemical and photophysical properties of the complexes are studied and electroluminescent devices are fabricated. The results show that the complexes with ligands containing carbazole moieties have desirable phosphorescent properties. The device with complex 3 doped PVK (poly (vinylcarbazole)) as emission layer achieves maximum luminous efficiency of 6.56 cd A−1 and maximum brightness of 14448 cd m−2.