Purely Organic Materials with Aggregation‐Induced Delayed Fluorescence for Efficient Nondoped OLEDs

Abstract Purely organic emitters with high exciton utilization have attracted considerable attention in the field of organic light‐emitting diodes (OLEDs). However, most reported thermally activated delayed fluorescence (TADF) emitters suffer from concentration quenching and exciton annihilation, so that they require complicated doping technique in OLED application. Nonetheless, the serious efficiency roll‐off remains a big challenge for doped OLEDs of TADF emitters. To simplify the fabrication process and improve the stability of devices, developing organic emitters for nondoped OLEDs is of high significance. This progress report provides a systematic summary and comments on the recent advances of efficient organic luminescent materials including conventional TADF materials and novel aggregation‐induced delayed fluorescence (AIDF) luminogens for the fabrication of high‐performance nondoped OLEDs. Their molecular design strategies, photophysical properties, and electroluminescence performances in nondoped OLEDs are elucidated in depth. The newly emerged organic materials with AIDF nature could be a promising direction for exploring light‐emitting materials to advance efficiency and stability of OLEDs.