Accession Number : ADA330250
Title : Interface Control of Polymer Based Light Emitting Devices.
Descriptive Note : Technical rept.,
Corporate Author : OHIO STATE UNIV COLUMBUS DEPT OF PHYSICS
Personal Author(s) : Epstein, A. J. ; Wang, Y. Z. ; Gebler, D. D.
PDF Url : ADA330250
Report Date : 20 SEP 1997
Pagination or Media Count : 14
Abstract : Bilayer and multilayer polymer structures provide opportunities for new photophysics and new types of light emitting devices. Photoluminescent and electroluminescent studies of bilayer heterojunctions formed from a poly(pyridyl vinylene phenylene vinylene) (PPyVPV) derivative and poly(vinyl carbazole) (PVK) show an emission peak which cannot be ascribed to either the PPyVPV derivative of PVK layer. Through studies of absorption and photoluminescence excitation (PLE) spectra we demonstrated that the additional feature results from an exciplex at the bilayer interface. The photoluminescence efficiency of the exciplex 5 greater than 20%. We also discuss here the fabrication of color variable bipolar ac light emitting devices based on conjugated polymers. The devices consist of blends of pyridine-phenylene and thiophene-phenylene based copolymers sandwiched between the emeraldine base form and the sulfonated form of polyaniline. ITO and Al are used as electrodes. The devices operate under either polarity of driving voltage with different colors of light being emitted, red under forward bias, and green under reverse bias.
Descriptors : *ELECTROLUMINESCENCE, *PHOTOLUMINESCENCE, *COPOLYMERS, HETEROJUNCTIONS, EMISSION SPECTRA, PYRIDINES, ANILINES, POLYVINYLIDENES, POLYPHENYLENES, AZOLES.
Subject Categories : Polymer Chemistry
Distribution Statement : APPROVED FOR PUBLIC RELEASE