Green phosphorescent organic light-emitting devices based on wide bandgap host materials

Two homoleptic iridium(III) complexes Ir3F and Ir6F were synthesized and tested as wide bandgap organometallic hosts for green phosphorescent OLEDs. While using Ir(ppy)3 as the green triplet emitter, Ir3F-based devices clearly outperformed similar devices fabricated with the traditional CBP host. On the opposite, Ir6F-based devices showed lower performances than the reference device. As appealing feature, Ir6F-based devices showed almost no efficiency roll-off i.e., no reduction of the luminous efficiency with the current density contrarily to that commonly observed for phosphorescent OLEDs.