Synthesis and characterization of blue-emitting, distyrylstilbenes bearing electron affinitive dendrons

Novel dendron-substituted distyrylstilbenes (OPV-R) in which electron affinitive moieties are on the outer surface of polyether type dendrons have been synthesized for blue-light emission. Both theoretical and optical investigations show that the polyether type dendrons attached at the non-conjugated meta-positions of a distyrylstilbene skeleton do not disrupt the coplanarity of the π-conjugated core. In addition, the dendron-substituted distyrylstilbenes show very high fluorescence quantum yields (over 90%). Single-layer light-emitting diodes using OPV-R doped poly(N-vinylcarbazole) (PVK) film as an emissive layer with structure of (ITO/OPV-R:PVK/Al) were fabricated and investigated. The emission wavelengths and spectral features are very similar among the solution emission, photoluminescence and electroluminescence spectra.