Performance improvement of white phosphorescent organic light-emitting diodes by using composite host structure to enhance the carrier injection

Abstract

Device characteristics of phosphorescent OLEDs with composite host structure were investigated by co-doping hole and electron transport-type hosts in emitting layer. The improved of charge injection and the confined of triplet excitons within recombination zone were achieved. White-OLED shows the efficiencies of 34.5 cd/A and 24 lm/W at 1000 cd/m(2).