White-electrophosphorescent devices based on copper complexes using 2-(4-biphenylyl)-5-(4-tert-butyl-phenyl)-1,3,4-oxadiazole as chromaticity-tuning layer
Document Type
Article
Publication Date
5-21-2006
Abstract
Efficient white organic light-emitting diodes based on copper complex, [Cu(bis[2-(diphenylphosphino)phenyl]ether)(6,7-dicyanodipyrido[2,2- d: 2′, 3′ -f] quinoxaline)] B F4 [Cu(I) complex], in which the white emission composed of yellow emission from Cu(I) complex doped 4, 4′ -N, N′ -dicarbazole-biphenyl (CBP) layer and blue emission from N, N′ -diphenyl- N, N′ -bis(1-naphthyl)- (1, 1′ -benzidine)- 4, 4′ -diamine layer, were fabricated. A thin 2-(4-biphenylyl)-5-(4-tert-butyl-phenyl)-1,3,4- oxadiazole (Bu-PBD) layer sandwiched between the two emission layers acts as a chromaticity-tuning layer. The white device with 10 nm, 2 wt % Cu(I) complex doped CBP layer and 2 nm Bu-PBD layer shows CIE coordinates of (0.33,0.36) at applied bias of 10 V, a maximum luminance of 2466 cd m2, and a maximum current efficiency of 6.76 cdA, corresponding to the power efficiency of 3.85 lmW. The efficient white emission is attributed to the simultaneous exciton formation in both emission layer. The working mechanism of the thin Bu-PBD layer for achieving white emission was also discussed. © 2006 American Institute of Physics.
Publication Source (Journal or Book title)
Applied Physics Letters
Recommended Citation
Su, Z., Che, G., Li, W., Su, W., Li, M., Chu, B., Li, B., Zhang, Z., & Hu, Z. (2006). White-electrophosphorescent devices based on copper complexes using 2-(4-biphenylyl)-5-(4-tert-butyl-phenyl)-1,3,4-oxadiazole as chromaticity-tuning layer. Applied Physics Letters, 88 (21) https://doi.org/10.1063/1.2207489