Optical characteristics of organic light emitting diode with IrQ(ppy)2–5Cl and its emitter

The synthesis and photophysical study of a cyclometalated mixed-ligand iridium(III) complex are reported. The iridium complex (called IrQ(ppy)2–5Cl) has two cyclometalated 2-phenylpyridine (ppy) ligands and one 8-hydroxyquinoline (Q) ligand, where one of the H atom is substituted by Cl atom. Absorption and photoluminescence spectra are studied for the neat film and films of IrQ(ppy)2–5Cl doped in 4,4′-N,N′-dicarbazole-biphenyl and polystyrene, together with the electroluminescence spectra using multi-layer light emitting devices. The electronic states are studied using density functional theory calculations. Emission bands are observed at 502 and 666 nm, which arise from ppy and Q ligands, respectively.