Improvement of efficiency roll-off in blue phosphorescence OLED using double dopants emissive layer

Blue phosphorescent organic light-emitting diodes (PHOLEDs) were fabricated using double dopants FIrpic and FIr6 in emissive layer (EML) with structure of ITO/NPB (700Å)/mCP:FIrpic-8%:FIr6-x% (300Å)/TPBi (300Å)/Liq (20Å)/Al (1200Å). We optimized concentration of the second dopant FIr6 in the presence of a fixed FIrpic to observe its effect on electrical performance of PHOLED device. 24.8cd/A of luminous efficiency was achieved by the device …