Blue pyrene-based AIEgens: inhibited intermolecular π–π stacking through the introduction of substituents with controllable intramolecular conjugation, and high external quantum efficiencies up to 3.46% in non-doped OLEDs

Abstract

Six blue AIE luminogens, Py-2pTPE, Py-2mTPE, Py-2TP, Py-2TF, Py-2NTF and Py-2F, have been successfully synthesized, which exhibit sky blue (484 nm) to deep blue (444 nm) emissions in accordance with the different introduced aromatic substituents on the pyrene core and the different linkage modes. Furthermore, Py-2pTPE and Py-2mTPE show interesting mechanochromism effects, inherited from TPE-pBr and TPE-mBr, respectively. When fabricated as emitters in OLEDs, all of the six AIEgens demonstrate blue emissions and good EL performances, among which, Py-2TP shows the best device performance with an η_EQE,max up to 3.46% at a CIE coordinate of (0.15, 0.09).