Dual-functional conjugated polymers based on trifluoren-2-yl-amine for RGB organic light-emitting diodes
作者:Hua Ye、Baofeng Zhao、Ming Liu、Xiao Zhou、Yanhu Li、Dongyun Li、Shi-Jian Su、Wei Yang、Yong Cao
DOI:10.1039/c1jm13533c
日期:——
A series of blue-light-emitting conjugated polymers that possess high-lying HOMO energy levels were synthesized by introducing trifluoren-2-yl-amine (TFA) as a building block. The emission color could be effectively tuned in the region of deep-blue and light-blue by introducing various substituents onto the TFA as the pendants. Deep-blue light emission was achieved for the device based on P4FNCz as an emitting layer without using any hole-transport layer (HTL), giving a maximum current efficiency (CE) of 2.44 cd A−1, corresponding to an external quantum efficiency of 3.00%, with Commission Internationale de L'Eclairage (CIE) coordinates of (0.16, 0.12). Thanks to the improved hole injection and transport ability, red- and green-light-emitting devices based on P4FNCz as an HTL were also successfully fabricated, giving a maximum CE of 7 and 25 cd A−1 with CIE coordinates of (0.64, 0.34) and (0.29, 0.64), respectively, which are comparable to those of the devices based on a general HTL of 4,4′-bis(N-(1-naphthyl)-N-phenylamino)biphenyl (NPB). The CIE coordinates of the RGB devices are very close to those of the National Television System Committee (NTSC) and High Definition Television (HDTV) standard colors. The RGB devices achieved by tuning the carrier recombination zone with different electron-transport layers will facilitate the development of the polymer-based full-color flat-panel displays in an alternative process.
通过引入三芴-2-基胺(TFA)作为构建基块,合成了一系列具有高位HOMO能级的蓝光发光共轭聚合物。通过在 TFA 上引入不同的取代基作为基团,可以有效地调节深蓝和浅蓝区域的发射颜色。基于 P4FNCz 作为发光层的器件在不使用任何空穴传输层(HTL)的情况下实现了深蓝色光发射,最大电流效率(CE)为 2.44 cd A-1,相当于 3.00% 的外部量子效率,国际照明委员会(CIE)坐标为(0.16, 0.12)。由于空穴注入和传输能力的提高,以 P4FNCz 为 HTL 的红光和绿光发光器件也被成功制作出来,其最大 CE 值分别为 7 cd A-1 和 25 cd A-1,CIE 坐标分别为 (0.64, 0.34) 和 (0.29, 0.64),与基于 4,4′-双(N-(1-萘基)-N-苯基氨基)联苯(NPB)的一般 HTL 的器件相当。RGB 设备的 CIE 坐标与美国国家电视系统委员会 (NTSC) 和高清晰度电视 (HDTV) 标准色彩的 CIE 坐标非常接近。通过调整不同电子传输层的载流子重组区而实现的 RGB 器件将有助于以替代工艺开发基于聚合物的全彩平板显示器。