Acta Phys. -Chim. Sin. ›› 2008, Vol. 24 ›› Issue (06): 977-980.doi: 10.1016/S1872-1508(08)60043-1

• ARTICLE • Previous Articles     Next Articles

Bright White Organic Light-Emitting Diode Mixed Blue and Green Emission

MA Tao; JIANG Ya-Dong; YU Jun-Sheng; LOU Shuang-Ling; LI Lu; ZHANG Qing   

  1. State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, P. R. China; Department of Polymer Science and Engineering, School of Chemistry and Chemical Technology, Shanghai Jiao Tong University, Shanghai 200240, P. R. China
  • Received:2007-11-19 Revised:2008-02-28 Published:2008-06-03
  • Contact: YU Jun-Sheng;ZHANG Qing E-mail:jsyu@uestc.edu.cn;qz14@sjtu.edu.cn

Abstract: Double-layer and triple-layer organic light-emitting diodes (OLEDs) were fabricated using a novel star-shaped hexafluorenylbenzene organic material, 1,2,3,4,5,6-hexakis(9,9-diethyl-9H-fluoren-2-yl)benzene (HKEthFLYPh) as an energy transfer layer, N,N’-bis-(1-naphthyl)-N,N’-diphenyl-(1,1’-biphenyl)-4,4’-diamine (NPB) as a hole-transport layer (HTL) and blue emissive layer (EML), and tris (8-hydroxyquinoline)aluminum (Alq3) as an electron-transport layer (ETL) and green light-emitting layer. Bright white light was obtained with a triple-layer device structure of indium-tin-oxide (ITO)/NPB (40 nm)/HKEthFLYPh (10 nm)/Alq3 (50 nm)/Mg:Ag (200 nm). A maximum luminance of 8523 cd·m-2 at 15 V and a power efficiency of 1.0 lm·W-1 at 5.5 V were achieved. The Commissions Internationale de L’Eclairage (CIE) coordinates of the device were (0.29, 0.34) at 9 V, which located in white light region. With increasing filmthickness of HKEthFLYPh, light emission intensity fromNPB increased compared to that of Alq3.

Key words: White organic light-emitting diode (WOLED), Star-shaped hexafluorenylbenzene, HKEthFLYPh, Energy transfer

MSC2000: 

  • O644