(4,4′-N, N′-dicarbazole) biphenyl (CBP) as Efficient Host in Cost-Effective Green Phosphorescent OLEDs

Abstract

(4,4'-N, N'-dicarbazole) biphenyl (CBP) serves as an efficient host material in the phosphorescent organic light emitting diodes (PHOLEDs) based on green-emitting Ir(ppy)(3) dopant with relatively low-cost charge transporting layers, resulting the higher device efficiencies of 31.45 cd/A, 10 %, and 11.3 lm/W with the maximum luminance of 60,170 cd/m(2) with highly improved efficiency roll-off when compared to those (24.08 cd/A, 7.98 %, and 14.16 lm/W with a maximum luminance of 19,090 cd/m(2)) of 9,9'-bis-(9,9-dimethyl-9H-fluoren-2-yl)-9H, 9'H-[ 3,3'] bicarbazolyl (BDFC) host based device.