Synthesis, Aggregation‐Induced Emission, and Electroluminescence of Dibenzothiophene‐ and Dibenzofuran‐Containing Tetraarylethenes

Abstract Dibenzothiophene‐ and dibenzofuran‐functionalized ethanes were synthesized by the McMurry coupling reaction. The luminogens are faintly emissive when molecularly dissolved in good solvents, but emit intensively when aggregated as nanoparticles in poor solvents or fabricated as solid thin films, demonstrating the phenomenon of aggregation‐induced emission (AIE). Their organic light‐emitting diode (OLED) applications were explored, utilizing the AIE effect. Electroluminescence devices with the configuration of indium tin oxide (ITO)/ N,N′ ‐di(1‐naphthyl)‐ N,N′ ‐diphenyl‐(1,1′‐biphenyl)‐4,4′‐diamine (NPB; 60 nm)/dye (20 nm)/1,3,5‐tri(1‐phenyl‐1 H ‐benzo[ d ]imidazol‐2‐yl)phenyl (TPBi; 10 nm)/tris(8‐hydroxyquinoline)aluminum (Alq 3 ; 30 nm)/LiF (1 nm)/Al (100 nm) were fabricated. The OLED device emits at 510 nm with a maximum luminescence and external quantum efficiency of 10 4 cd/m 2 and 2.1 %, respectively. The OLED behavior of the E / Z isomers was also studied.