Synthesis, photoluminescence properties of novel cationic Ir(III) complexes with phenanthroimidazole derivative as the ancillary ligand

Two novel cationic Ir(III) complexes, [(nbt)2Ir(L)](PF6) and [(CF3-bt)2Ir(L)](PF6), where nbt = 2-(1-naphthyl)benzothiazole; CF3-bt = 2-phenyl-6-(trifluoromethyl)-benzothiazole and L = 1-(4-(tert-butyl)phenyl)-2-(5-(9-(p-tolyl)-9H-carbazol-3-yl)pyridin-2-yl)-1H-phenanthro [9,10-d]imidazole, were successfully synthesized and characterized. The structures of L and [(nbt)2Ir(L)](PF6) were confirmed by single crystal X-ray diffraction. Their photophysical, electrochemical properties and thermal stabilities were investigated systematically. The results showed that the Ir(III) complexes had higher thermal stabilities, and exhibited strong red emission and orange emission, respectively.