A series of distyrylbenzene (DSB) derivatives, as the oligomeric analogue of poly-p-phenylenevinylene (PPV), were synthesized and assessed as the emitter in organic light emitting diode (OLED) fabrication. The presence of an electron-withdrawing cyano group and an electron-donating methoxy group was studied at various positions in the molecule to evaluate their influence on the photophysical properties and the electroluminescent behavior of these derivatives in OLED. Bright blue emissions were achieved with these materials, as dopant, in a device of structure ITO/NPB/CBP/TPBI ∶ DSB/TPBI/Mg ∶ Ag, where NPB, CBP, and TPBI stand for 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl, 4,4′-dicarbazolyl-1,1′-biphenyl and 2,2′,2″-(benzene-1,3,5-triyl)tris-[1-phenyl-1H-benzimidazole], respectively.
There was not much difference in the absorption and emission spectra of the compounds containing n-hexyloxy and 2-ethylhexyloxy groups. However, 2-ethylhexyloxy groups produce a more saturated blue color in their EL. The compounds 1–6 with higher fluorescence quantum yield did not result in higher EL quantum efficiency in this multilayer OLED fabrication as that of 7–9 with lower fluorescence quantum yield.
研究人员合成了一系列
二苯乙烯苯(DSB)衍
生物,它们是聚对
苯乙烯(PPV)的低聚类似物,并将其作为有机发光二极管(OLED)制造中的发光体进行了评估。我们研究了分子中不同位置上的一个电子吸收
氰基和一个电子捐赠甲氧基,以评估它们对这些衍
生物在有机发光二极管中的光物理特性和电致发光行为的影响。在一个结构为 ITO/NPB/CBP/TPBI ∶ DSB/TPBI/Mg ∶ Ag(其中 NPB、CBP 和 TPBI 分别代表 4、NPB、CBP 和 TPBI)的装置中,这些材料作为掺杂剂实现了明亮的蓝色发射、4′-双[N-(1-
萘基)-N-苯基
氨基]
联苯、4,4′-二
咔唑基-1,1′-
联苯和 2,2′,2″-(苯-1,3,5-三基)三[1-苯基-1H-
苯并咪唑]。
含有正己氧基和 2-乙基己氧基的化合物的吸收光谱和发射光谱差别不大。不过,2-乙基己氧基基团产生的 EL 蓝色饱和度更高。荧光量子产率较高的 1-6 号化合物与荧光量子产率较低的 7-9 号化合物相比,在这种多层有机发光二极管制造中并没有产生更高的 EL 量子效率。