Pyrene‐Based Blue Aggregation‐Induced Emission Luminogens: The Synergistic Effect of Through‐Space Conjugation for High Exciton Utilization Efficiency and Narrow‐Band and Blue OLEDs

Abstract Achieving outstanding narrow‐band emission and improving the triplet exciton utilization efficiency is crucial for high organic light‐emitting diodes (OLEDs) electroluminescence (EL) efficiency. Herein, novel 1,3‐asymmetrical substituted pyrene‐based blue “hot exciton” materials with aggregation‐induced emission (AIE) characteristics are synthesized, utilizing the pyrene ring's staggered energy levels for high‐performance OLEDs. The triphenylamine‐decorated pyrene‐based blue emitters exhibited narrow full width at half maxima (FWHM) < 60 nm, while the tetraphenylethylene‐decorated compounds displayed a higher fluorescence quantum yield but broader FWHM emission in the film state. These AIE luminogens (AIEgens) show good EL efficiency and high exciton utilization efficiency (>35.6%) in nondoped OLED devices. Meanwhile, both triphenylamine‐decorated and tetraphenylethylene‐decorated pyrenes are further utilized as an emitter layer in thermally activated delayed fluorescence (TADF)‐sensitized blue OLEDs with great EL performance. Moreover, the TPE‐decorated pyrene‐based TPE‐ m 2Ph demonstrated a maximum brightness, maximum current efficiency, maximum power efficiency, and maximum external quantum efficiency of 35230 cd m ⁻² , 42 cd A ⁻¹ , 48 lm W ⁻¹ , and 14.9%, respectively.