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 $[{\mathrm{Ir(ppy)}}_3]$ as a triplet emissive dopant in poly(vinylcarbazole) (PVK) host. The device with 8% doping concentration of $[{\mathrm{Ir(ppy)}}_3]$ in PVK showed the external quantum efficiency of 1.9% and the peak luminance of 2,500 ${\mathrm{cd/m}}^2.$ The emission spectrum of the device exhibited no emission from PVK, indicating that the energy transfer from PVK to $[{\mathrm{Ir(ppy)}}_3]$ is efficient. This work demonstrates that efficient electrophosphorescent light-emitting devices can be realized with polymers.