Recent advances of NIR-TADF (λmaxPL/EL &gt

Abstract

The rise of organic thermally activated delayed fluorescence (TADF) materials as NIR emitters and hosts have engrossed wide consideration as they can demonstrate 100% internal quantum efficiency. These materials have exceeded the phosphorescent noble-metal complexes due to cost-efficiency without compromising the OLED performance. Numerous applications of the NIR spectrum, e.g., in telecommunication, night-vision display, biomedical applications, and chemical sensors, render the NIR-TADF emitters vulnerable to evolution. This review highlights the various strategies adopted in the recent past (2015-2022) to judiciously design purely organic NIR-TADF emitters (λmaxPL/EL &gt

700 nm) with in-depth discussions of photophysical and device-electroluminescence studies. Approaches such as the incorporation of extended π-conjugated acceptors, diazoles of group-16 elements, ‘BF2’-acceptor, non-conjugated donor-acceptor dendrons, exciplex formation, and TADF sensitization provide effective pathways to construct high-efficiency NIR-TADF-OLEDs. Thus, this review aims to provide a new perspective for the next generation researchers to implement strategies for the thoughtful design of efficient NIR-TADF materials. © 2022 The Royal Society of Chemistry.