Multi-carbazole encapsulation as a simple strategy for the construction of solution-processed, non-doped thermally activated delayed fluorescence emitters

Two TADF emitters are developed via the introduction of carbazole dendrons into the multi-positions of a blue TADF emissive core. By utilizing these TADF emitters as the non-doped solution-processed emissive layers, the resulting greenish-blue OLED achieves a peak EQE of 12.2%, which is among the highest values for non-doped solution-processed fluorescent OLEDs. Multi-carbazole encapsulation is demonstrated as a simple strategy for the development of solution-processed TADF emitters. The resulting OLED achieves a high external quantum efficiency of 12.2% for non-doped solution-processed fluorescent OLEDs.