新一代有机电致发光材料突破激子统计

Progress in next-generation organic electroluminescent materials:Material design beyond exciton statistics

激子(或自旋)统计是基本的物理原理,决定有机半导体器件中形成单线态与三线态激子的比例(1:3).近年来,基于新原理(三线态反系间窜越、延迟荧光)的OLED材料引起广泛关注.该类材料在理论方面重新催热了关于自旋统计的探讨,在应用方面有望发展成为低成本、高性能的新一代OLED材料,在国内相关领域得到重视,多个研究机构已布局开展相关研究.从目前的发展情况看,该类材料的发光机制、原理以及进一步材料设计思路还有待探讨和明确.鉴于此,本文综述了激子统计研究进展,分析了多种提高激子利用效率的途径,提出本课题组提高激子利用率的"热激子过程"新思路及杂化局域-电荷转移(HLCT)态材料设计原理,器件实现接近100%的激子利用效率.

Exciton （or spin） statistics is a basic physical principle, which determines the singlet and triplet excltons ratio （1：3） formed in an organic semiconductor device. In recent years, the OLED materials based on new principles （reverse intersystem crossing, delayed fluorescence） received widespread attentions in this field. This kind of materials rejuvenates the spin-statistics theory, and it is expected to develop into a low-cost, high-performance next-generation OLED materials. Domestic researchers in organic optoelectronics also attached great importance to it, and a number of research institutions have conducted research arrangement in this field. From the current development situation, the emitting mechanisms, principles and materials design ideas of this material are yet to be further explored and clear. In this review, we review the progress of the exciton statistics, and analyze a variety of ways to improve exciton utilization efficiency. Furthermore, we propose the ＂hot exciton＂ new ideas and material design principles to improve exciton utilization, and the devices harvest the exciton utilization efficiency close to 100%.