Study of the white organic electroluminescent devices performance based on phosphorescent dyes FCNIrPic

Abstract

Two kinds of high efficient white-light OLED devices based on blue phosphorescent material FCNIrPic(Bis(3,5-difluoro-4-cyano-2-(2-pyridyl)phenyl-(2-carboxypyridyl) iridium(III))) were fabricated by means of the principle of whitening with blue-yellow complementary colors. Firstly, white-light device A was fabricated by the hybrid of yellow fluorescent material Rubrene and blue-light layer of phosphorescent FCNIrPic. The device structure is ITO/m-MTDATA/NPB/Rub/MCP: FCNIrPiC/Alq3/LiF/Al. The structure of the device is optimized by adjusting the thickness of phosphorescent doping layer MCP: FCNIrPiC. When the thickness of blue layer is 8 nm, the device has the best performance. The maximum brightness is 13240 cd/m2 and the maximum current efficiency is 3.5 cd/A. The color coordinates are near (0.33, 0.37) and change little with the increase in voltage. Secondly, white OLED device B with double phosphorescent layer was fabricated by yellow phosphorescent PO-01 and FCNIrpic. The device structure is ITO/m-MTDATA/NPB/CBP: PO-01/MCP: FCNIrpic/Alq3/LiF/Al. White light was obtained by adjusting the thickness of blue layer. When the thickness of blue layer is 10 nm, the device has the best performance. The maximum current efficiency is 9.8 cd/A and the maximum brightness is 11 400 cd/m2. The color coordinates are near (0.33, 0.35).