Efficient white organic light-emitting devices using 4,7-diphenyl-1,10-phenanthroline as block layer

详细信息	查看全文 | 推荐本文 |

• 作者：Huishan Yang ; Yanwei Shi ; Yi Zhao ; Jingying Hou ; Shiyong Liu
• 关键词：External quantum efficiency ; White organic light-emitting device ; Hole-blocking layer ; Color stability
• 刊名：Journal of Luminescence
• 出版年：2007
• 期刊代码：54_00222313
• 类别：ch
• 出版时间：December 2007
• 卷：127
• 期：2
• 页码：367-370
• 文件大小：228 K

摘要

A white light-emitting device has been fabricated with a structure of ITO/m-MTDATA (45 nm)/NPB (10 nm)/DPVBi (8 nm)/DPVBi:DCJTB 0.5%(15 nm)/BPhen (x nm)/Alq₃ [(55−x) nm]/LiF (1 nm)/Al, with x=0, 4, and 7. BPhen was used as the hole-blocking layer. This results in a mixture of lights from DPVBi molecules (blue-light) and DCJTB (yellow-light) molecules, producing white light emission. The chromaticity can be readily adjusted by only varying the thickness of the BPhen layer. The CIE coordinates of the device are largely insensitive to the driving voltages. When the thickness of BPhen is 7 nm, the device exhibits peak efficiency of 6.87 cd/A (3.59 lm/W) at the applied voltage of 6 V, the maximum external quantum efficiency η_ext=2.07%corresponding to 6.18 cd/A, and the maximum brightness is 18494 cd/m² at 15 V.