Organic light-emitting diodes exploiting aggregation-induced exciton and exciplex emissions

The derivatives of carbazole and tetraphenylethylene exhibiting aggregation-induced emission and 4,4‧,4‧-tris[3-methylphenyl(phenyl)amino]triphenylamine were used for the preparation of organic light-emitting diodes the electroluminescence spectra of which include exciton and exciplex emissions. The low-energy exciplex emission of the electroluminescence spectrum was formed at the interface of the emissive layers. The best fabricated device showed turn-on voltage of 2.7V for electroluminescence (at 10cd/m²); maximum current efficiency of 11.5cd/A, maximum brightness of 17,700cd/m² (at 11V), and external quantum efficiency of ca. 3.9% with CIE 1931 chromaticity coordinates (0.20, 0.38).