采用绿色溶剂制备有机发光二极管铝酞菁阳极缓冲层的研究

GREEN SOLVENT PROCESSED ALUMINUM PHTHALOCYANINE DERIVATIVES AS ANODE BUFFER LAYERS IN ORGANIC LIGHT-EMITTING DIODES

郑璐萍

11649168

硕士

化学工程

许宗祥

2018

2018.7.6

哈尔滨工业大学

深圳

随着电子信息技术的 发展和人们消费 水平和 需求的 提高，市场对显示器 的各项性能 不断提出新 的 要求：高色彩饱和度、快速响应、低能耗、轻质、柔性等。有机发光二极管（ Organic light-emitting diode OLED）因 满足人们对显示器所提出的一系列要求而激发了 越来越多的研究兴趣 。 目前该领域 发展迅速 已经逐渐开始 工业化 ，部分小型的屏幕已经成功应用在手机的显示器上了 。然而，问题依然存在，如难以实现大面积湿法制备，器件寿命及稳定性相对较差等，大大限制了其推广应用。此外，目前 采用溶液法制备有机半导体器件的各功能层时， 主要采用苯、甲苯、二甲苯、氯仿氯苯、二氯苯等含苯、含卤素的溶剂， 对工作人员的健康以及对环境都造成了严重的威胁。 因而，开发绿色环保的器件制备方法是立足长远，实现 OLED行业可持续发展，造福人类未来的必由之路。本研究从分子设计角度出发，选用以及合成了一系列铝酞菁材料，如非取代铝酞菁 AlPc）、 α位四甲基取代铝酞菁 AlMePc 和 α位八甲基取代铝酞菁 AlMe2Pc等，利用该类型酞菁可分散于绿色醇类溶剂的特点，通过超声技术，制备铝酞菁纳米颗粒，所得平均粒径分别为 79 nm (AlPc)、 13 nm (AlMePc)和 26 nm (AlMe2Pc)。采用液相旋涂技术，以纳米酞菁的绿色分散液制备 OLED阳极缓冲层，系统研究酞菁 分子结构、纳米颗粒形貌、溶剂体系、分散液浓度及旋涂工艺参数等对薄膜性能及器件性能的影响规律。结果表明， AlMePc阳极缓冲层表面粗糙度小，能有效覆盖修饰 ITO阳极，且透光性能好，在此基础上制备 Alq3发光二极管，获得了11790 cd/m2发光亮度、 4.74 cd/A电流效率和 2.81 lm/W发光效率，相比广泛使用的 PEDOT:PSS阳极缓冲层，实现了器件效率及寿命的显著提高。从工业化角度分析，溶液处理方法是大面积加工、降低生产成本的更好选择，因而应用前景广阔。本研究进一步利用 AlMePc的抗溶剂性，以 之为阳极缓冲层PDY-132为发光层，采用全溶液方法成功制备聚合物发光二极管（ PLED），获得94.98 cd/m2的 发光亮度 0.063 cd/A的 电流效率和 0.038 lm/W的 发光效率，是基于酞菁阳极缓冲层全溶液方法制备 PLED的首次探索。

Organic light-emitting diode (OLED) has attracted more and more research interest during the last three decades due to the advantages such as high color saturation, light weight, flexibility, fast response and so on. However, challenges still remain, for instant, relatively low power efficiency, relatively poor device stability and lifetime, and technical difficulties in large-scale production via solution process. Moreover, the organic electronic devices are currently processed using toxic halogenated solvents such as chlorobenzene, 1,2-dichlorobenzene, and chloroform, which are detrimental to the environment and to human health. Indeed, the replacement of these highly toxic solvents with environmentally friendly or green solvents is urgently needed in OLED fabrication.In this thesis, a series of metal phthalocynines (MPc) have been synthesized and characterized, namely unsubstituted aluminum phthalocynine (AlPc), tetramethyl-substituted aluminum phthalocyanine (AlMePc) and octamethyl-substituted aluminum phthalocyanine (AlMe2Pc). These MPcs can be well dispersed in a green solvent system (a mixture of ethanol and butanol) via ultrasonication to produce a stable dispersion, in which phthalocyanine nanostructures can form, giving the average particle sizes of 79 nm, 13 nm and 26 nm for AlPc, AlMePc and AlMe2Pc, respectively. The resulting dispersion can be directly used for the fabrication of OLED anode buffer layers via spin-coating. It was found that the ITO surface was covered well by AlMePc, forming a relatively smooth and continuous film morphology. A typical tris(8-hydroxyquinoline)aluminum (Alq3)-based OLED was fabricated to examine the AlMePc layer quality. The enhancements in luminance (11790 cd/m2), luminous efficiency (4.74 cd/A) and power efficiency (2.81 lm/W) were obtained for the AlMePc-based diode compared with that of the PEDOT:PSS-based one. Furthermore, the improved charge balance in the OLED achieved by using the AlMePc layer along with its non-aqueous, organic processing methods yielded a maximum half-lifetime of 1860 min under a driving current density of 100 mA/cm2.Also, the spin-coated AlMePc thin films are insoluble in common organic solvents, providing a solvent-resistant layer that facilitates solution processing of further thin films on top of it to afford a multilayered device configuration, which is of vital importance for the preparation of all-solution-processed polymer light-emitting diodes (PLEDs). Thus, in this work, a PLED using the AlMePc anode buffer layer and PDY-132 emissive layer was fabricated via all-solution-processed method, and the luminance of 94.98 cd/m2, the current efficiency of 0.063 cd/A as well as the power efficiency of 0.038 lm/W were obtained. The research presented a preliminary feasibility investigation of the fabrication of all-solution-processed PLED using MPc anode buffer layer.

铝酞菁 绿色溶剂 纳米颗粒 有机小分子器件 有机聚合物发光二极管 阳极缓冲层

Aluminum Phthalocyanine Nano-particles organic small molecule Organic Light-Emitting Diode Polymeric Light-emitting Diodes Anode Buffer Layer

中文

联合培养

南方科技大学

郑璐萍. 采用绿色溶剂制备有机发光二极管铝酞菁阳极缓冲层的研究[D]. 深圳. 哈尔滨工业大学,2018.