Emerging hyperfluorescent emitters for solid-state lighting

Organic light-emitting diodes (OLEDs) are of high interest for display, biomedical, and solid-state lighting applications. However, costs and color purity are still issues with the OLED technology. The development of triplet harvesting emitters with a thermally activated delayed fluorescence (TADF) mechanism mends these problems to some extent, owing to their ability to produce both singlet and triplet excitons. In addition, the recent development of hyperfluorescent OLEDs (HF-OLEDs) based on TADF and fluorescent emitter couples has attracted a lot of attention, realizing high efficiency, good stability, and narrow emission. In this mini-review, we comprehensively documented the molecular design principles of hyperfluorescent emitters, their fundamental photophysics, and the advances in their applications in OLEDs. Finally, the future prospects of hyperfluorescent emitters and OLEDs are discussed. This paper highlights the molecular design principles of hyperfluorescent emitters, their fundamental photophysics, and the advances of their applications in OLEDs.