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Open Access Article

Physical Sience and Technical Research. 2022; 2: (1) ; 22-31 ; DOI: 10.12208/j.pstr.20220004.

Research progress of blue exciplex-based organic light-emitting materials
蓝光激基复合物有机发光材料的研究进展

作者: 龚河旗 *, 李智, 张金成, 刘辉, 郭强, 李杰

成都信息工程大学 四川成都

*通讯作者: 龚河旗,单位:成都信息工程大学 四川成都;

发布时间: 2022-06-30 总浏览量: 856

摘要

近年来,基于激基复合物的有机发光材料广泛应用于有机发光二极管(OLED),受到学术界和产业界越来越多的关注,尤其是具有热活性延迟荧光(TADF)特性的激基复合物有机发光材料。由于激基复合物的最低激发单重态(S1)和最低激发三重态(T1)之间的能级差(ΔEST)小,T1激子可以通过反向系间窜越(RISC)转变为S1激子,然后辐射出光子,实现TADF发射。激基复合物通常是偏空穴传输性质的给体(D)材料和偏电子传输性质的受体(A)材料之间的物理混合。在光致发光和电致发光过程中,激基复合物可以通过D-A之间的电荷转移(CT),增强发光效率从而提高器件的发光性能。目前,越来越多的激基复合物有机发光材料被应用于OLED,其中发展较快的是绿光和红光激基复合物,而蓝光激基复合物发展缓慢。这主要是因为蓝光激基复合物还存在一些亟待解决的缺陷,例如稳定性较差、器件寿命较短以及发光效率较低。本文对蓝光激基复合物有机发光材料的发光原理、设计原则以及最新进展进行了简要综述,并对其未来发展作出展望。

关键词: 激基复合物;有机发光材料;延迟荧光;反向系间窜越

Abstract

Exciplex-based organic light-emitting materials have received much attention over recent years, especially exciplexes with thermally activated delayed fluorescence (TADF) properties. The energy difference (ΔEST) of an exciplex between the lowest excited singlet state (S1) and the lowest excited triplet state (T1) is usually small. Triplet excitons can be converted to be singlet excitons through reverse intersystem crossing (RISC), and then radiate photons to achieve TADF. An exciplex is a physical mixture between a donor (D) with hole transport properties and an acceptor (A) with electron transport characteristics. In the processes of photoluminescence and electroluminescence, exciplexes can enhance the luminescence efficiencies and subsequently improve the device performance by means of D-A charge transfer (CT). At present, more and more exciplex-based organic light-emitting materials are applied to organic light-emitting diodes (OLEDs). Thereinto, a number of green and red exciplexes are developed, while blue exciplexes are relatively few. This is mainly because there are still some defects to be solved in blue exciplexes, such as poor stability, short device lifetime and low luminous efficiency. In this paper, the luminescence principle, design principle and the latest progress of blue exciplex-based organic luminescent materials are briefly reviewed, and their future development is prospected.

Key words: Exciplex; Organic light-emitting material; Delayed fluorescence; Reverse intersystem crossing

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引用本文

龚河旗, 李智, 张金成, 刘辉, 郭强, 李杰, 蓝光激基复合物有机发光材料的研究进展[J]. 物理科学与技术研究, 2022; 2: (1) : 22-31.