柔性大面积长寿命量子点LED的设计、构造与性能研究

Currently, quantum dot light-emitting diodes (QLED) have attracted increasing interest due to their narrow emission linewidth, tunable colour emission, stability as well as cost-effective fabrication techniques compatible with solution processed methods. In the past few years, with the rapid development of QLEDs in performance, the research on QLEDs has become a hot topic in the field of advanced displays. To solve the issues of the poor performance and short operating lifetime in current QLED devices, in this project, we intend to make use of our accumulated knowledge/experience, around the key issues and technical challenges for flexible QLEDs in device performance, to investigate the aspects of the preparation of highly efficient functional materials, novel design of device structure and encapsulation of flexible device in depth, aiming at grasping the control methods for improving flexible device performance and understanding related mechanisms. Our research will also devote to the development for all-solution processed large-area flexible QLEDs, meeting the modern requirements of low-cost and large-area production process. Through the implementation of the project, we hope that there will be a breakthrough in the key issues for the physics and techniques associated with functional materials, device structure, fabrication process, operating lifetime and manufacturing cost, and thus promote the China self-innovation research and industrialization for flexible QLEDs.

量子点发光二极管(QLED)具有发光纯度高、颜色易调节、稳定性好、兼容溶液加工等诸多优点，近年来随着其性能取得了突破性进展，QLED已成为当前新型显示领域的研究热点。本项目针对当前柔性QLED器件性能低、工作寿命短的现状，充分利用已有的工作基础，围绕影响柔性QLED器件性能的关键问题和技术难题，从高效功能材料制备，新型器件结构设计、柔性器件封装等多方面进行深入系统的研究，旨在掌握提高柔性电子器件性能的调控手段并理解相关影响机制。本研究还致力于开发全溶液过程制备大面积柔性QLED器件的新技术，满足现代化低成本、大面积的生产工艺要求。希望通过本项目的实施，力争在柔性QLED器件所涉及的功能材料、器件结构、加工工艺、使用寿命、制造成本等关键物理与技术问题上有所突破，为我国自主创新的柔性QLED器件研究与产业化发展做出贡献。

量子点发光二极管(QLEDs)以其发射光谱窄、发光亮度高、颜色易调节、制备成本低等一系列优点而受到了极大的关注，成为了下一代发光显示领域的研究热点。近年来随着其性能取得了突破性进展，QLED已成为当前新型显示领域的研究热点。本项目针对当前柔性QLED器件性能低、工作寿命短的现状，充分利用已有的工作基础，围绕影响柔性QLED器件性能的关键问题和技术难题，从高效功能材料制备，新型器件结构设计、柔性器件等多方面进行深入系统的研究，在以下三个方面取得了创新成果：.A、高性能柔性QLED器件：通过将红/绿/蓝量子点以一定比例混合作为发光层，精确控制量子点之间的荧光共振能量转移效应，实现了纯白光发射的QLED器件，色坐标为（0.34，0.33）。此外，所制备柔性白光QLED器件最大亮度达到3554 cd/m2，电流效率达到10.5 cd/A；同时，通过采用串联结构连接红/绿/蓝三种发光单元，并设计合适的器件结构以改善载流子注入平衡，进一步实现了高效的白光QLED器件，最大电流效率和外量子效率分别达到79.9 cd/A和28%。.B、高效长寿命QLED器件：采用稳定性的金属氧化物NiO代替有机半导体PEDOT:PSS作为器件载流子传输层，运用p型掺杂技术优化载流子的注入和平衡输运，所制备QLED器件的外量子效率为10.5%，通过用Cu:NiO薄膜替代PEODT:PSS材料，量子点器件的操作使用寿命被延长了几乎四倍。此外还采用铜掺杂磷钨酸代替PEDOT:PSS作为空穴注入层，实现了接近20%外量子效率的倒置QLED器件，器件寿命相比基于PEDOT:PSS的QLED寿命高5倍。..此外，本项目还研究了多种高效长寿命大面积QLED器件，包括全无机QLED器件，串联结构QLED器件，以及钙钛矿LED器件等。