Fabrication and spectra characteristics of high efficiency white organic light-emitting diodes with single emitting layer

High-efficiency white organic light-emitting devices with single emitting layer are demonstrated. N,N’- diphenyl-N,N’-bis(1,1’-biphenyl)-4,4’-diamine (NPB) is used as hole transport layer, while 4,7-diphenyl-1,10-phenan- throline (BPhen) as electron transport layer and 9,10-di- (2-naphthyl)-2-terbutyl-anthracene (TADN) doped with the fluorescent dye 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7- tetramethyljulolidyl-9-enyl) (DCJTB) as single emissive layer. The effects of performance by the concentration of DCJTB and the thickness of emissive layer are studied. The device with a structure of indium tin oxide/NPB (50 nm)/TADN: 0.2% DCJTB (15 nm)/BPhen (40 nm)/Mg: Ag shows a maximum brightness of 11400 cd/m2, a peak current effi-ciency of 5.6 cd/A and power efficiency of 4.1 lm/W, while the low turn-on voltage of 3.1 V and the stability of the Commis-sion International De LEclairage coordinate. The spectra through color filter of the device are also studied.