NIR TADF emitters and OLEDs: challenges, progress, and perspectives
Yuxin Xiao, Hailan Wang, Zongliang Xie, Mingyao Shen, Rongjuan Huang, Yuchen Miao, Guanyu Liu, Tao Yu, Wei Huang
Abstract
Recently, thermally activated delayed fluorescence (TADF) emitters have made historic developments in the field of OLEDs. These metal-free materials are more attractive because of efficient reverse intersystem crossing processes which result in promising high efficiencies in OLEDs. However, the development of NIR TADF emitters has progressed at a relatively slower pace which could be ascribed to the difficult promotion of external quantum efficiencies. Thus, increasing attention has been paid to NIR TADF emitters. In this review, the recent progress of NIR TADF emitters has been summarized along with their molecular design strategies and photophysical properties, as well as electroluminescence performance data of their OLEDs, respectively.