Organic emitters have been widely developed since the demonstration of high efficiency in pure organic emitters represented by thermally activated delayed fluorescent (TADF) emitters. Pure organic‐based TADF emitters are found to harvest all singlet and triplet excitons for radiative transition processes, like phosphorescent emitters that utilize all generated excitons for light emission by strong spin–orbit coupling. Red, green, and blue organic emitters are investigated, but major interest is focused on green and blue organic emitters. However, recent studies are being directed to red and even near‐infrared emitters because of their wide applications in bioimaging, sensors, telecommunications, and night vision. Although the external quantum efficiency of the red and near‐infrared TADF organic light‐emitting diodes (OLEDs) is low, the external quantum efficiency of red OLEDs has been advanced to close to 30% and that of near‐infrared OLEDs to the 10% level. Therefore, more attention is being paid to red and near‐infrared TADF emitters. In this work, recent progress of the red and near‐infrared TADF emitters is reviewed to understand the molecular design principle and the molecular structure–photophysical characteristics and molecular structure–device performance relationships. In addition, future prospect of the red and near‐infrared TADF emitters is proposed.

中文翻译：

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高效红色和近红外热激活延迟荧光发射体的最新进展

自从以热激活延迟荧光（TADF）发射器为代表的纯有机发射器获得高效率证明以来，有机发射器得到了广泛的发展。发现基于纯有机物的TADF发射器可收集所有单重态和三重态激子用于辐射跃迁过程，例如磷光发射体，它利用所有产生的激子通过强自旋-轨道耦合来发光。对红色，绿色和蓝色有机发射器进行了研究，但主要关注点是绿色和蓝色有机发射器。但是，由于其在生物成像，传感器，电信和夜视中的广泛应用，最近的研究针对红色甚至近红外发射器。尽管红色和近红外TADF有机发光二极管（OLED）的外部量子效率很低，红色OLED的外部量子效率已提高到接近30％，近红外OLED的外部量子效率已提高到10％的水平。因此，人们越来越关注红色和近红外TADF发射器。在这项工作中，对红色和近红外TADF发射器的最新进展进行了综述，以了解分子设计原理以及分子结构-光物理特性和分子结构-器件性能之间的关系。此外，还提出了红色和近红外TADF发射器的未来前景。回顾了红色和近红外TADF发射器的最新进展，以了解分子设计原理以及分子结构-光物理特性和分子结构-器件性能之间的关系。此外，还提出了红色和近红外TADF发射器的未来前景。回顾了红色和近红外TADF发射器的最新进展，以了解分子设计原理以及分子结构-光物理特性和分子结构-器件性能之间的关系。此外，还提出了红色和近红外TADF发射器的未来前景。