Efficient electrophosphorescence from low-cost copper(I) complex

Light-emitting devices, using a high-phosphorescent copper(I) complex [Cu(phen)(POP)]PF6 [POP = Bis-[(2-diphenyl-phosphino)phenyl]ether and phen = 1,10-phenanthroline] as dopant and emitting center have been investigated, in different device architectures involving single layer devices using the blend of poly(N-vinylcarbazole) (PVK) and 2-tert-butylphenyl-5-biphenyl-1,3,4-oxadiazol (PBD) as host and heterostructure multi layer devices using PVK as host. The maximum luminance of the phosphorescent devices reached 1400 cd/m2 and the highest luminance efficiency exceeded 1 cd/A for single layer devices and higher luminescence efficiency up to 1.8 cd/A for multi layer ones. Efficient electrophosphorescent OLEDs can be developed by using low-cost Cu(I) complex as guest and polymer as host material.