化学学报 ›› 2012, Vol. 70 ›› Issue (18): 1904-1908.DOI: 10.6023/A12060324 上一篇    下一篇

研究论文

一种具有稳定发射光谱的高效率白色有机电致发光器件

周亮, 邓瑞平, 郝召民, 宋明星, 张洪杰   

  1. 中国科学院长春应用化学研究所 稀土资源利用国家重点实验室 长春 130022
  • 投稿日期:2012-06-19 发布日期:2012-08-06
  • 通讯作者: 张洪杰
  • 基金资助:

    项目受国家自然科学基金(No. 21071140)和国家自然科学基金创新研究群体项目(No. 20921002)资助.

Efficient White Electroluminescent Device with Stable Emission Spectrum

Zhou Liang, Deng Ruiping, Hao Zhaomin, Song Mingxing, Zhang Hongjie   

  1. State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022
  • Received:2012-06-19 Published:2012-08-06
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No. 21071140) and National Natural Science Foundation for Creative Research Group (No. 20921002).

报道一种具有稳定发射光谱的新型白色有机电致发光器件. 选择DCJTB 作为红光染料将其掺入空穴传输材料NPB 中作为空穴传输层和第一发光层, 提供蓝光和红光; 选择AlQ 作为电子注入敏化剂, 将其掺入NPB 中作为第二发光层, 提供蓝光和绿光. DCJTB和AlQ 的掺杂浓度分别被优化为0.4%和1.4%, 第二发光层的厚度被优化为3 nm. 最终,得到了纯白色发射的有机电致发光器件; 该器件启亮电压仅3.1 V, 最大亮度高达32749 cd/m2, 器件的最大电流效率为8.67 cd/A, 器件的最大功率效率为8.78 lm/W. 而且, 空穴型主体材料的选择导致该器件的色稳定性非常理想. 随着电流密度的提高, 该器件的色坐标始终稳定在(0.343, 0.342)到(0.328, 0.336)的范围内.

关键词: 电致发光, 荧光材料, 电子注入, 载流子复合, 发光效率

In this work, we report a novel white organic light-emitting device (WOLED) with stable emission spectrum. Red emitter 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) was selected and doped into N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-diphenyl-4,4'-diamine (NPB) layer as hole transport layer and the first light-emitting layer (EML1), which provides blue and red emissions. The widely used green material tris(8-hydroxyquinoline) aluminum (AlQ) was selected as sensitizer of electron injection and doped into NPB layer as the second light-emitting layer (EML2), which provides blue and green emissions. The doping concentrations of DCJTB and AlQ were optimized to be 0.4% and 0.14%, respectively, while the thickness of EML2 was optimized to be 3 nm. Finally, we obtained the pure white organic light-emitting device, which possesses 3.1 V turn-on voltage, 32749 cd/m2 maximum brightness, 8.67 cd/A maximum current efficiency, and 8.78 lm/W maximum power efficiency. More importantly, the use of hole-type host material help to confine the recombination zone of holes and electrons, thus improving the stability of electroluminescent spectrum. With increasing current density, the Commission Internationale de l’Eclairage (CIE) coordinates of this device change from (0.343, 0.342) to (0.328, 0.336).

Key words: electroluminescence, fluorescent material, injection of electrons, recombination of carriers, luminescent efficiency