Novel carbazole dendronized oligofluorenes for solution-processed organic light-emitting diodes

•Dendrimers were synthesized by attaching carbazole dendrons to an oligo-fluorene core.•They have good film-forming ability by solution method.•They were used as non-doped emitter to fabricate organic light-emitting diodes.•The solution-processed devices exhibited pure blue emission with CIE (0.16, 0.08).

A group of novel dendrimers containing an oligofluorene core and oligo-carbazole dendrons, were synthesized by a Suzuki cross-coupling reaction. The dendrimers exhibit excellent thermal and amorphous stabilities, and emit deep blue fluorescence with high quantum yields of over 85%. These molecules have non-planar molecular conformations and thus possess excellent solubility and film-forming ability by solution-processing techniques. The dendrimers are used as hole-transporting emitting layers to fabricate organic light-emitting diodes (OLEDs) by a spin coating process. Bright deep blue electroluminescence is obtained with CIE coordinates of ca. (0.16, 0.09), which are quite close to the National Television System Committee (NTSC) standard blue coordinates of (0.14, 0.08). Maximum luminances were in the range of 388–711 cd m−2 and maximum luminance efficiencies were in the range of 0.91–1.07 cd A−1 for the derived devices.

Graphical abstractNovel carbazole-based dendrimers are developed for use as non-doped emitters in solution-processed organic light-emitting diodes, which exhibit deep-blue electroluminescence with Commission Internationale de l'Eclairage (CIE) coordinate y < 0.1.Figure optionsDownload full-size imageDownload as PowerPoint slide