Highly Twisted Thermally Activated Delayed Fluorescence (TADF) Molecules and Their Applications in Organic Light-Emitting Diodes (OLEDs)

Thermally activated delayed fluorescence (TADF) materials have attracted great potential in the field of organic light-emitting diodes (OLEDs). Among thousands of TADF materials, highly twisted TADF emitters have become a hotspot in recent years. Compared with traditional TADF materials, highly twisted TADF emitters tend to show multi-channel charge-transfer characters and form rigid molecular structures. This is advantageous for TADF materials, as non-radiative decay processes can be suppressed to facilitate efficient exciton utilization. Accordingly, OLEDs with excellent device performances have also been reported. In this Review, we have summarized recent progress in highly twisted TADF materials and related devices, and give an overview of the molecular design strategies, photophysical studies, and the performances of OLED devices. In addition, the challenges and perspectives of highly twisted TADF molecules and the related OLEDs are also discussed.

Automated summary

Thermally activated delayed fluorescence (TADF) materials, particularly highly twisted TADF emitters, have shown great potential in the field of organic light-emitting diodes (OLEDs). These highly twisted TADF emitters exhibit multi-channel charge-transfer characters and rigid molecular structures, suppressing non-radiative decay processes and enhancing exciton utilization for efficient OLED performance. This review summarizes recent progress, molecular design strategies, photophysical studies, and device performances of highly twisted TADF materials and OLEDs, while also discussing the challenges and future prospects in this area.