Aggregation‐induced narrowband isomeric fluorophores for ultraviolet nondoped OLEDs by engineering multiple nonbonding interactions

Traditional donor-acceptor type organic luminescent materials usually suffer from unfavorable spectral broadening and fluorescence quenching problems arising strong inter/intra-chromophore interactions in aggregation state. Here, two ultraviolet carbazole-pyrimidine isomers (named o-DCz-Pm m-DCz-Pm) with novel aggregation-induced narrowband phenomenon are constructed systematic investigated by experiments theoretical simulations. Benefitting strengthened steric hindrance multiple noncovalent interactions, the nonradiative decay, vibrational motion, structural relaxation of singlet state can be effectively suppressed Consequently, electroluminescence peak 397 nm, full width at half maximum 21 nm external quantum efficiency 3.4% achieved simultaneously nondoped o-DCz-Pm-based device. This work paves an avenue toward development high-performance light-emitting diodes.