Efficient deep-blue emitters based on triphenylamine-linked benzimidazole derivatives for nondoped fluorescent organic light-emitting diodes

•Deep-blue fluorescent emitters were synthesized for efficient nonpoded OLEDs.•The effect of packing density on the device performances was studied.•The device exhibited high efficiency of 4.67% with deep-blue color of (0.15, 0.08).

Two triphenylamine-substituted benzimidazole derivatives were synthesized for use as efficient deep-blue emitters in nondoped fluorescent organic light-emitting diodes (FLOLEDs). The molecular design of 4′,4′′-(1H-benzo[d]imidazole-1,2-diyl)bis(N,N-diphenylbiphenyl-4-amine) (T2B) to limit the molecular packing density enabled T2B-based devices to suppress the exciton quenching by a bulky three-dimensional structure. Nondoped FLOLEDs fabricated using T2B as a blue emitter exhibited an external quantum efficiency of 4.67% with color coordinates of (0.15, 0.08).

Graphical abstractLimited molecular packing density of the emitter suppresses the exciton quenching, thereby increasing an external quantum efficiency of T2B-based nondoped fluorescent OLEDs.Figure optionsDownload full-size imageDownload as PowerPoint slide