Highly efficient red electrophosphorescent device based on a new iridium complex with trifluoromethyl-substituted 2-benzo[b]thiophen-2-yl-pyridine ligand

We report a new red Ir(III) complex, (btfmp)2Ir(acac), with the trifluoromethyl-substituted 2-benzo[b]thiophen-2-yl-pyridine ligand. Efficient red electrophosphorescence with CIE coordinates (x = 0.69, y = 0.29) independent on current density was observed from the (btfmp)2Ir(acac) doped devices. The electroluminescent (EL) spectrum has a maximum at λmax = 648 nm. Maximum external quantum efficiency of 9.6% at current density of 0.125 mA/cm2 and 3.7% at J = 100 mA/cm2 were obtained.