Polymer phosphorescent light-emitting devices doped with tris(2-phenylpyridine) iridium as a triplet emitter

We have fabricated phosphorescent polymer light-emitting devices with tris(2-phenylpyridine) iridium $[Ir(ppy)3]$ as a triplet emissive dopant in poly(vinylcarbazole) (PVK) host. The device with 8% doping concentration of $[Ir(ppy)3]$ in PVK showed the external quantum efficiency of 1.9% and the peak luminance of 2,500 $cd/m2.$ The emission spectrum of the device exhibited no emission from PVK, indicating that the energy transfer from PVK to $[Ir(ppy)3]$ is efficient. This work demonstrates that efficient electrophosphorescent light-emitting devices can be realized with polymers.