可印刷型结晶诱导发光及热激活延迟荧光材料与器件效率研究

Display printing technique is an important development direction for display technique in future, and it is possible that a large-scale, thin, flexible light-emitting devices and displays can be printed like newspaper. The development of printing technique and its practical application largely depend on the performances of organic fluorescence material, which is the critical part in the display. The aggregation-caused quenching problem (ACQ) must be properly tackled, because the luminophores are commonly used as solid films in their practical applications. Aggregation-induced emission（AIE） effect are a good strategy for resolving this problem. The thermally activated delayed fluorescence (TADF) emitters have now been accepted as the third generation of OLEDs emitters after the conventional fluorescence and phosphorescence materials, because its internal quantum efficiency can be reached to 100 % in theory. In this project, a series of groups: tetraphenylethylene, triphenylamine，tert-butyl group and so on, which posses the AIE，TADF and good solubility properties, are going to be incorporated into 8-Hydroxyquinoline ligand. Then the ligands continue to be in coordination with Zn2+, Al3+by hydrothermal method in order to get the printable crystallized fluorescence Materials. Then the relationships among the molecular structures and optoelectronic properties are hopeful to be recognized through systemically investigating of light intensity，efficiency and lifetime of the device. In the end, we hope to get some excellent printable fluorescence materials, which can resolve the ACQ problem, improve the efficiency of device and reduce production costs.

印刷显示技术是未来显示技术发展的重要方向，最终可达到“像印报纸一样制造显示器”，实现大面积、轻、薄、柔性的显示。有机发光材料作为有机发光器件中的关键成分，其性能很大程度上决定了印刷显示技术的发展及其实用化进程。聚集诱导发光效应为减少有机薄膜发光材料荧光猝灭，提高发光器件效率提供了全新的分子设计思路。热激活延迟荧光材料是继有机荧光和有机磷光材料之后发展的第三代有机发光材料，其器件的内量子效率理论上可以接近100%。本项目结合前期工作基础及最新的印刷显示研究进展，提出将具有聚集诱导发光和热激活延迟荧光效应的四苯基乙烯、三苯胺等共轭基团以及叔丁基等具有良好溶解性的官能团引入8-羟基喹啉配体，再利用水热法与锌、铝等过渡金属进行配位, 构筑可印刷型的晶态金属有机材料，系统研究材料结构与器件效率的关系，并筛选出性能优异的发光材料用于器件。预期不仅有效解决固态荧光猝灭难题，而且提高器件效率和降低成本。

聚集诱导发光效应为减少有机薄膜发光材料荧光猝灭，提高发光器件效率提供了全新的分子设计思路。热激活延迟荧光材料是继有机荧光和有机磷光材料之后发展的第三代有机发光材料，其器件的内量子效率理论上可以接近100%。然而，可印刷型结晶诱导发光及热激活延迟荧光材料仍然较少而且相关研究存在以下问题：合成方法与提纯方法的研究不足，不能满足其商业化大规模生产的要求；发光机理的研究相对比较薄弱，尤其是分子空间结构与材料性能之间的关系还需要大量的研究工作；结晶诱导发光的高效发光材料设计较为困难。本项目针对上述发展困境，四苯乙烯、芳基酮、菲并咪唑、咔唑、8-羟基喹啉类材料为活性基团，以高效有机合成方法学为主要手段，构建了多个系列的高效有机光电材料，并详细研究了材料结构与性能之间的关系，获得了一系列成果：实现了热活化延迟荧光和室温磷光双发射的可控调节、获得以四苯乙烯为核心的高效聚集诱导发光新型发光材料、对比度高和选择性专一聚集诱导发光效应荧光探针、具有结晶诱导发光性能的摩擦发光变色材料、基于推拉电子性质的大共轭咪唑-芴深高效蓝光材料、高发光性能的8-羟基喹啉类金属配合物等。本项目的实施为设计高效有机光电材料提供了有益思路。