Rayappa Naveen Kenkera, Prabhu Cp Keshavananda, Braveenth Ramanaskanda, Hyuk Kwon Jang
Organic Optoelectronic Device Lab (OODL), Department of Information Display, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, Seoul, 02447, Republic of Korea.
Chemistry. 2022 Feb 24;28(12):e202103532. doi: 10.1002/chem.202103532. Epub 2022 Jan 12.
Pure organic molecules based thermally activated delayed fluorescence (TADF) emitters have been successfully developed in recent years for their propitious application in highly efficient organic light emitting diodes (OLEDs). In the case of orange red emitters, the non-radiative process is known to be a serious issue due to its lower lying singlet energy level. However, recent studies indicate that there are tremendous efforts put to develop efficient orange red TADF emitters. In addition, the external quantum efficiency (EQE) of heteroaromatic based orange red TADF OLEDs surpassed 30 %. Such heteroaromatic type emitters showed wide emission spectra; therefore, more attention is being paid to develop highly efficient orange red TADF emitters along with good color purity. Herein, the recent progress of orange red TADF emitters based on molecular structures, such as cyanobenzene, heteroaromatic, naphthalimide, and boron-based acceptors, are reviewed. Further, our insight on these acceptors has been provided by their photophysical studies and device performances. Future perspectives of orange red TADF emitters for real practical applications are discussed.
近年来，基于纯有机分子的热激活延迟荧光（TADF）发光体因其在高效有机发光二极管（OLED）中的良好应用而被成功开发。就橙红色发光体而言，由于其单重态能级较低，非辐射过程被认为是一个严重问题。然而，最近的研究表明，人们为开发高效橙红色TADF发光体付出了巨大努力。此外，基于杂芳族的橙红色TADF OLED的外量子效率（EQE）超过了30%。这种杂芳族类型的发光体显示出较宽的发射光谱；因此，在开发具有良好色纯度的高效橙红色TADF发光体方面，人们给予了更多关注。在此，本文综述了基于分子结构（如氰基苯、杂芳族、萘二甲酰亚胺和硼基受体）的橙红色TADF发光体的最新进展。此外，通过对这些受体的光物理研究和器件性能，提供了我们对它们的见解。讨论了橙红色TADF发光体在实际应用中的未来前景。
