Blue emitting diodes based on self-assembled multilayers of cationic oligo(p-phenylene vinylene) and sulfonated polyaniline

Boladication form oligo(p-phenylene vinylene) (OPV) was synthesized and mixed boladication–polyanion multilayer thin films have been self-assembled by a process based on electrostatic interaction. Electroluminescent spectral fine structures of these self-assembled thin films showed differences in vibronic coupling intensity and space. The poly(aniline-co-N-propane-sulfonic acid aniline) (PAPSAH) provided better charge transport ability than poly(sulfonated styrene) (PSS) and the turn-on voltage of the device based on boladication OPV/PAPSAH multilayer thin films is lower than that of the PSS counterpart.