【作者】 黄锦海；

【导师】 苏建华；

【作者基本信息】 华东理工大学 ， 应用化学， 2011， 博士

【摘要】 有机电致发光器件(Organic light-emitting diodes, OLEDs)作为下一代显示器之一,并可以用在环保照明上,已经成为国际上竞争最激烈的前沿科学领域和非常热门的新兴平板显示器及照明产业。有机电致发光材料在有机电致发光器件中起了非常重要的作用,其性能很大程度地影响了器件产业化的进程。因此,研究和探索符合市场化要求的有机电致发光材料具有重大意义。蒽类化合物具有刚性结构、宽能隙和高荧光量子效率,同时又具有良好的成膜性、稳定性和适当的载流子传输性质等优点,使其备受关注,在有机电致发光器件中具有很好的实际价值和应用前景。本文就是基于蒽类衍生物良好的光电性质,通过在其9、10位或其他碳原子上进行取代修饰,引入各种官能团,合成了一系列功能化的蒽衍生物,并把它们应用在电致发光器件上来研究它们的性能。本文具体研究内容和研究成果包括如下几个方面：第一章综述了有机电致发光器件的基本概念、性能参数、器件结构、研究进展,同时也对蒽类衍生物的研究发展与应用做了详细的介绍。第二章通过在蒽的9,10位引入三苯胺和苯并咪唑基团,合成并表征了一系列具有空穴传输功能和电子传输功能的两性有机电致蓝光材料。这些化合物具有很高的热稳定性和较高的量子效率。通过测量发现这些化合物的荧光光谱具有很强的溶剂化效应,并测试了这些化合物在甲苯和四氢呋喃中的双光子荧光性能。制作三种类型器件分别研究这些化合物的发光性能、电子传输性能和空穴传输性能,化合物B1,B2和B4的器件发射蓝光,而化合物B2由于电子异构体的形成,导致在低电流密度(<5mA/cm2)下发射白光。由化合物B4做成的单层器件,在电流密度为20 mA/cm2下的电流效率为3.33 cd/A,CIE(x,y)值为(0.16,0.16),在8.7 V的驱动电压下的发光亮度为8472 cd/m2。第三章合成了两种不对称的无定型的9,10-二取代的蒽类衍生物。这两个化合物发射蓝光,具有很好的热稳定性,它们的玻璃化温度分别为132.5和133.8℃。通过电子扫描显微镜来研究这两个化合物的薄膜的形态稳定性,相比较对称的MADN,这两个化合物都具有更好的稳定性。用这两个同分异构体作为发光层制作的器件,发射蓝光,当以它们为主体发光层,掺杂一种天蓝光BUBD-1的客体材料时,得到了天蓝光的器件。通过改变电子传输层和空穴传输层,我们系统地研究了这两个材料,并制得一系列高效的蓝光器件。第四章合成并表征了一系列含有以三聚茚为核的蒽类衍生物。这些化合物发射蓝光,具有很高的溶液荧光量子效率,它们的热分解温度超过460℃,并随着分子量的增大而提高。用化合物NPAT作为发光层制作了结构为ITO/CFx/NPAT/TPBI or Alq3/LiF/Al的电致发光器件,通过调节发光层和电子传输层的厚度来优化器件。第五章把苯并咪唑接在蒽的9,10位上,合成了一个含蒽的电子传输材料。通过循环伏安测得这个材料的HOMO和LUMO分别为5.7 eV和2.7 eV。并作为电子传输材料应用在绿光和蓝光的掺杂器件上,通过跟经典的电子传输材料Alq3比较来研究化合物的电子传输性能。为了更好地研究目标化合物的电子传输和电子注入性能,制作了electron-only和electron-injection两种类型的器件。第六章介绍了一系列以MADN为底物,在蒽的2位上引入不同官能团,如具有电子传输功能的苯并咪唑、空穴传输性能的三苯胺的蒽衍生物。这些基团的引入不仅可以有效地调节光的颜色和化合物的热稳定性,还可以使这些化合物兼有发光功能和电荷传输性能。第七章介绍了两个含有六苯基苯的空穴传输材料。第八章总结了本论文的主要工作和内容。更多还原

【Abstract】 Organic light-emitting diodes (OLEDs) have drawn great scientific and commercial attention in the past decades, due to their potential applications in full-color, flat-displays as well as solid-state lighting. The electroluminescent materials play a very important role in OLEDs, which largely affect the process of industrialization of OLEDs. Therefore, it is very important to study and explore the high-efficiency and stable materials. Anthracene derivatives have been intensively studied and applied in OLEDs, due to their rigid structure, high energy gap, high fluorescent quantum yield, amorphous thin film morphology, excellent thermal stability, balanced carrier mobility, as well as easier modification. Moreover, the anthracene derivatives are focused on the application because of their practical value and prospects in OLEDs.In this thesis, a series of functionalized anthracene derivatives by introducing different groups at the 9,10 or other positions of anthracene unit based on fantastic electro-optical properties of anthracene derivatives were synthesized and characterized, also were applied in OLEDs to study their electroluminescent properties. The main research contents and results were generalized as follows:In chapter 1, the basic concept, property parameter, device structure and recent progress of organic light-emitting diodes are reviewed. Especially, the development and application of anthracene derivatives were particularly introduced.In chapter 2, a series of bipolar anthracene derivatives containing hole-transporting triphenylamine and electron-transporting benzimidazole moieties were synthesized and characterized. These compounds possess high thermal properties and quantum yield in toluene solution, but their photoluminescence spectra are sensitive to the polarity of the solvent. The two-photon excited fluorescence characteristics of the bipolar anthracene derivatives in both toluene and THF solution have been measured. Three types of devices were fabricated to investigate their electron-transporting, hole-transporting as well as light-emitting properties. The electroluminescent spectra for the three derivatives B1, B3 and B4 show that they emit blue light, while the B2-based devices produced white light at a low current density because of the electromer formation. Moreover, a single layer OLED device for B4 exhibited a current efficiency of 3.33 cd/A with a pure blue color of CIE(x,y) of (0.16, 0.16) at 20 mA/cm2 and a maximum brightness of 8472 cd/m2 at 8.7 V.In chapter 3, two unsymmetrically amorphous 9,10-disubstituted anthracene derivatives have been synthesized and characterized. They emit the light in the blue region and possess glass transition temperature of 132.5℃and 133.8℃. The scanning electron microscope (SEM) was employed in studying the thin film morphological stability of the two unsymmetrical isomers. These two compounds were fabricated into typical trilayers devices with pure blue lighting performance. In addition, a series of highly efficient and stable sky blue devices doped with a sky blue dopant BUBD-1 have been fabricated by using these two isomers as the host.In chapter 4, a new series of anthracene derivatives containing a truxene moiety as the core have been synthesized and characterized. They emit in the blue region with excellent solution fluorescence quantum yields and possess high thermal decomposition temperature (Td>458℃). Typical electroluminescence performance was demonstrated by NPAT as the blue lighting material in the OLED with structure of ITO/CFx/NPAT/TPBI or Alq3/LiF/Al. Additionally, the effects of the different thickness of the different electron-transporting layers on the device performance were investigated.In chapter 5, we synthesized and characterized one electron-transporting material containing anthracene and benzimidazole moieties, and measured the HOMO energy level and LUMO energy level with 5.7 eV and 2.7 eV through cyclic voltammery (CV) analyses. The compound was applied in the green and blue devices as electron-transporting layer to achieve the better performance than those Alq3-based devices. The electron-only and electron-injection devices were also fabricated to study its electron-transporting and electron-injecting properties.In chapter 6, a new series of anthracene derivatives based on the common MADN by introducing the functional moiety including the triarylamine or benzimidazole at the 2 position of anthracene were synthesized and characterized. The introduced group can not only turn the emitting light and thermal stability, but also affect the emission and charge transporting properties of these materials.In chapter 7, two hole-transporting materials based on the hexaphenylbenzene were synthesized and characterized.The chapter 8 is conclusion更多还原