基于纳米金属氧化物的高效量子点发光二极管的研究

To solve the energy issues and fulfill the great strategic demand of the country, solid state lighting and display devices with less power consumption, long lifetime and no pollution is becoming an key roadmap for developing energy saving and environmental protection and low-carbon economy. It is also to boost new growth areas in the economy and seize the opportunity in the strategic emerging industry. Quantum dot light-emitting diode (QLED) inherits the advantages of light-emitting diode (LED) and organic light-emitting diode (OLED). Meanwhile, it can provide important way to achieve lighting and display devices with high-energy efficiency, high color rendering index, high color saturation and broadening working temperature range. In this project, based on two key scientific issues: elimination charge accumulation and improvement of the luminous efficiency in QLED devices; we propose metal oxide nano-materials can be chosen as hole and electron transportation layers which have matched energy band for QLED devices. The selection of these nanomaterials is to accelerate charge transportation rate, balance injected hole and electron in QD layer, reduce luminous quenching, enhance the work efficiency of QLED and improve the anti-corrosive ability of QLED device to resist oxygen, water to realize un-encapsulation unit. Meanwhile, by design and fabrication of surface plasmon model, the efficiency of quantum dot can be enhanced and realization of QLED device with surface plasma. The innovative achievements based on highly-efficient electro-optic conversion mechanism and enhancement of microstructure employed in QLED device, the project can explore a new route and provide technical support for the development of new lighting and display technology.

面向国家解决能源问题的重大战略需求，具有耗电量少、寿命长、无污染等特点的固态发光和显示器件已经成为节能环保、发展低碳经济的重要手段之一，也是培育新的经济增长点，抢占战略性新兴产业制高点的关键。量子点发光二极管继承了半导体发光二极管和有机发光二极管的性能优势，对进一步实现高能效、高显色指数、高色饱和度和宽工作温度的照明和显示器件提供了重要的发展方向。本项目针对如何消除量子点发光二极管器件中电荷积累和提高发光效率两个关键科学问题，提出采用能带匹配的纳米金属氧化物作为电荷传输层材料，平衡量子点上注入的电子与空穴，提高量子点发光二极管工作能效，并增强器件对氧气、水的抗腐蚀力，实现在无封装结构；设计和制备表面等离子体激元结构，进一步增强量子点的发光效能。本项目将在量子点发光二极管器件的高效电光转换机理及采用微纳结构增强发光效率等方面取得创新性成果，为发展新型照明和显示技术探索新道路和提供技术支撑。

本项目针对如何消除量子点发光二极管器件中电荷积累和提高发光效率两个关键科学问题,提出采用能带匹配的纳米金属氧化物作为电荷传输层材料,平衡量子点上注入的电子与空穴,提高量子点发光二极管工作能效,并增强器件对氧气、水的抗腐蚀力,实现在无封装结构;设计和制备表面等离子体激元结构,进一步增强量子点的发光效能。同时，研究与制备出倒置式发光二极管器件，为实现驱动电路一体化以及量子点器件的商业化进程迈出重要一步。研究成果包括：1)建立高效纳米金属氧化物量子点发光的理论模型；2)获得相应的红，绿，蓝，白光原型器件，并通过实验验证其高效发光效率机理；3)三色量子点荧光效率高于60%，QLED器件开启电压最低可达1.6 V，原型器件能效大于8 lm/W, 无封装器件工作寿命大于200小时;4) 发表SCI收录的国际学术期刊论文31篇，国际会议论文5篇，申请发明专利9项；5)培养博士研究生7名，硕士研究生11名。本项目在量子点发光二极管器件的高效电光转换机理及采用微纳结构增强发光效率等方面取得创新性成果，为发展新型照明和显示技术探索新道路和提供重要的技术支撑。