Investigation Of PPV Derivation And Luminescence Property

Organic thin film electroluminescence(EL), as new research field, has been a hot subject in flat panel displays and attracted more and more people. Higher and higher technology for information display is required as a result of rapid development of information technology. Display panel with rich color, low cost, environmentally protection, lightweight, even flexibility, has become a goal of modern people. Organic thin film electroluminescence would be an ideal technology for information display of modern times due to its low driving voltage, highly efficient luminescence, rich color, fast response, wide viewing angle, portability, etc. However, organic electroluminescence is by itself a subject relate to chemistry, material, physics, electronics etc., and need people to investigate it from material design and synthesis, device fabrication and its performance measurement, luminescence process and mechanism, etc.In this paper, the method of improving electroluminescence quantum yield is primarily investigated and the optical property of poly(2,5-dibutoxy)-1,4-phenylene vinylene(PDBOPPV) and poly[2-methoxy-5-(2'-ethyl-hexyloxy)1,4-phenylene vinylene](MEHPPV) are measured. At first, we introduce the basic process of photo-physics and photochemistry and electroluminescence mechanism. In this section, energy band structure, carrier injection, and energy transfer are expounded. And then, we explain the limitation of internal quantum yield 25%, and introduce four approach of improving electroluminescence quantum yield in theory, include doping phosphorescence dye, choosing magnetism material as electrode, doping transition metal complex, and using solid state cathodoluminescence. And then, the synthecic routes of PDBOPPV is introduced, butyloxy of poly (p-phenylene vinylene) can increase the solubility. The infrared spectra of PDBOPPV are characterized. From the spectra, the accurate configuration is found. Photoluminescence spectra and the luminescence property of solution of PDBOPPV and MEHPPV are investigated. In same material, the red-shift of wavelength is found with the increase of concentration, because of excimer. The wavelength of PDBOPPV is longer than that of MEHPPV, because the substituent of the two kinds of materials are different. The steric effect of PDBOPPV side chain is stronger than that of MEHPPV. The photoluminescence spectra are contrasted in different molecular weight, we find the large one have longer wavelength. Finally, the manufacture technology of electroluminescence devices are discussed. And the I-V characterization of the devices are investigated.