电场调控变色有机电致发光器件的结构设计和双向激子调控研究

High efficiency, long lifetime and effective cost are three critical elements of organic light-emitting devices (OLEDs) to realize mass productions in the fields of information displays and solid state lighting. Since the efficiency and lifetime of OLEDs have gradually met the requirements of industrialization, the cost, which is the last limitation of OLEDs to compete with other displays and lighting devices, becomes a key academic problem to be urgently solved. Aiming at solving the bottleneck of low qualified product rate and high cost, which are resulted from adopting various device configurations and functional materials for different colors, this project illuminates a color-tunable OLED controlled by electric fields. To realize the color-tunable OLED with low driving voltage, high luminance and wide gamut, the emission mechanisms and the methods of broadening the color tunable range are scheduled to demonstrate via fundamental researches. This research mainly includes: . 1. To build the color-tunable theoretical model and illuminate the corresponding mechanism; . 2. To investigate the effect of the transport mode of charge carriers and the dynamic process of bilateral exciton control on the color-tunable ability; . 3. To design functional materials and device configurations for novel and highly efficient bilateral exciton controlled layers; . 4. To study the technology of designing and fabricating the device with wide gamut and high color-tunable index, and finally realize the color-tunable OLEDs with the high luminance and big color-tunable index.

高效率、长寿命、低成本是决定有机电致发光器件（OLED）在新型显示和固态照明领域大规模应用的三个关键因素，器件的发光效率和使用寿命已在逐步满足产业化的要求，而成本是限制其与已有信息显示和照明器件竞争的重要因素，是目前亟待解决的一个关键科学问题。针对当前不同发光颜色器件的不同结构与不同功能材料导致的良率低、成本高的难题，本项目提出了一种通过改变电场强度实现颜色可调控的变色OLED器件，拟揭示电场调控变色OLED器件的发光机理，探讨提高变色范围的方法，实现低电场调控、高亮度、宽色域的变色OLED器件，研究内容主要包括：1、电场调控变色OLED器件的变色理论模型构建和变色机理研究；2、载流子传输模式和双向激子调控动态过程对变色能力的影响研究；3、新型高效双边激子调控层的功能材料和结构设计；4、宽色域和多变色类型的电场调控变色OLED器件的结构设计和制备。

针对当前不同发光颜色器件的不同结构与不同功能材料导致的良率低、成本高的难题，本项目提出了一种通过改变电场强度实现颜色可调控的变色OLED器件，拟揭示电场调控变色OLED器件的发光机理，探讨提高变色范围的方法，实现低电场调控、高亮度、宽色域的变色OLED器件，完成的内容包括：（1）电场调控变色OLED器件的变色理论模型构建和变色机理研究；（2）载流子传输模式和双向激子调控动态过程对变色能力的影响研究；（3）新型高效双边激子调控层的功能材料和结构设计；（4）宽色域和多变色类型的电场调控变色OLED器件的结构设计和制备。取得的重要成果有：系统性地研究了互补双发光层体系，探究了激子调控层在该发光体系中的作用机理，制备了一系列电控变色 OLED 器件。通过选取四种不同传输特性材料作为激子调控层，系统分析了不同材料、不同厚度调控层对器件变色及发光性能产生的影响，揭示了电控变色器件中激子的传输机理以及发光过程的工作机理。使用热激活延迟荧光材料制备的基于橙色超薄非掺杂磷光层和蓝色重掺杂荧光层的混合型电控变色OLED，实现了高效率和光谱稳定，功率效率接近29 lm/W，流明效率超过33 cd/A，外量子效率大于16.5%。另外，提出了新型的钙钛矿发光二极管器件，其发光性能有望获得更高的效率。相关的研究结果共发表SCI论文38篇，申请发明专利16项，授权专利5项，培养硕士研究生17名，博士研究生13名。