Organic light emitting diode (OLED) is a new yet promising technology that is anticipated to replace the liquid crystal display technology in the very near future. The development of both the emitter and host materials for OLEDs is indispensable to realize high device efficiency and optimal performance. Though the presently commercialized OLED panels mostly utilize phosphorescence emitters, the all‐organic thermally activated delayed fluorescence (TADF) emitting materials have some obvious advantages. Considerable progress has been made in search of better performing TADF OLEDs in the past few years. Although major research attention has been drawn toward reporting new TADF emitters, the hosts are equally important in TADF OLEDs, as the doped films of the emitters mostly yield better results than the nondoped films. There are already some good reviews on the TADF emitters in literature. In this review article, the literature data specifically aimed at hosting TADF dopants are carefully selected and comprehensively summarized and categorized into several sub‐groups based on their structural features to draw the attention of the organic electronics research community toward developing new host materials for TADF OLEDs.

中文翻译：

---

热活化延迟荧光有机发光二极管的主体材料透视图

有机发光二极管（OLED）是一项新的但很有前途的技术，有望在不久的将来取代液晶显示技术。OLED的发射极和主体材料的开发对于实现高设备效率和最佳性能是必不可少的。尽管目前商业化的OLED面板主要使用磷光发射器，但全有机热激活延迟荧光（TADF）发射材料具有一些明显的优势。在过去几年中，在寻找性能更好的TADF OLED方面已经取得了可观的进步。尽管已经引起了对报告新型TADF发射器的主要研究关注，但是主体在TADF OLED中同样重要，因为发射器的掺杂薄膜通常比未掺杂的薄膜产生更好的结果。关于TADF发射器的文献已有一些不错的评论。在这篇综述文章中，专门针对TADF掺杂剂的文献数据经过精心选择，并根据其结构特征进行了综合归纳和归类为几个亚组，以引起有机电子研究界对开发用于TADF OLED的新型基质材料的关注。 。