Tetraphenylbenzene-based AIEgens: horizontally oriented emitters for highly efficient non-doped deep blue OLEDs and hosts for high-performance hybrid WOLEDs

Deep blue organic-emitting fluorophores are crucial for applications in white lighting and full color flat-panel displays but emitters with high color quality and efficiency are rare. Herein, novel tetraphenylbenzene (TPB) based deep blue AIE luminogens (AIEgens) with various donor units and the same acceptors of cyano groups are developed and used to fabricate non-doped deep blue and hybrid white organic light-emitting diodes (OLEDs). Benefiting from its high emission efficiency and high proportion of horizontally oriented dipoles in the film state, the non-doped deep blue device based on CN-TPB-TPA realizes a maximum external quantum efficiency of 7.27%, with low efficiency roll-off and CIE coordinates of (0.15, 0.08). Moreover, efficient two-color hybrid warm white OLEDs (CIEx,y = 0.43, 0.45) are achieved using CN-TPB-TPA as a blue-emitting layer and a phosphor doped host, which realize maximum current, power, and external quantum efficiencies of 58.0 cd A(-1), 60.7 lm W-1 and 19.1%, respectively. This work provides a general strategy to achieve high performance, stable deep blue and hybrid white OLEDs by the construction of AIEgens with an excellent horizontal orientation.