Fabrication of self-assembled multilayer heterostructure of poly(p-phenylene vinylene) and its use for an electroluminescent diode

Multilayer heterostructure thin films of electroactive polymers such as poly(p-phenylene vinylene) (PPV)-precursor and sulfonated polyaniline (SPAn) have been successfully fabricated via a process based on the spontaneous self-assembly of conjugated polyion on a substrate. We have prepared SPAn‖PPV multilayer heterostructure light-emitting diodes (LEDs) using this electrostatic self-assembly technique and discussed the electroluminescent (EL) properties. The SPAn‖PPV monolayer LED emits greenish-yellow light, but the SPAn‖PPV multilayer emits bluish-green light and there is a slight shift between the two spectra of these devices. These results can be interpreted in terms of the confinement effect of carriers in the superlattice structure consisting of a SPAn‖PPV multilayer system.