Endowing TADF Luminophors with AIE Properties Though Adjusting Flexible Dendrons for Highly Efficient Solution-Processed Nondoped OLEDs.
The amalgamation of thermally activated delayed fluorescence (TADF) and aggregation-induced emission (AIE) properties, term AIE-TADF, is a promising strategy to design novel robust luminescent materials. Herein, we transform 2,3,4,5,6-penta(9H-carbazol-9-yl)benzonitrile (5CzBN) from an ACQ molecule to AIEgens by simply decorating a 5CzBN core with alkyl chain-linked spirobifluorene dendrons. By increasing the number of flexible dendrons, these materials can not only show obvious AIE-TADF characteristics and uniform film morphology, but also exhibit better resistance to isopropyl alcohol, which are beneficial to the fully solution-processed OLEDs. Notably, 5CzBN-PSP show great device efficiency with external quantum efficiency (EQE), current efficiency and power efficiency of 20.1%, 58.7 cd A-1 and 46.2 lm W-1, respectively, which achieved record-breaking efficiency in solution-processed nondoped OLEDs based on AIE emitters. It demonstrates a general approach to explore new efficient emitters by the marriage of AIE and TADF what could potentially improve their performance in various areas.