The Fabrication Of Polymer Light Emitting Devices By Electropolymerization Methods

Polymer light emitting devices based on conjugated or non conjugated polymers have become extremely important areas of study. To fabricate the device,the polymer is usually prepared as a uniform thin film deposited onto an ITO electrode by spin-casting or dip-coating methods. This requires a good solubility of the polymer in an appropriate solvent. The writer thinks that direct film formation on ITO glass by electropolymerization provides options to avoid the problem.It is well known that the boron trifluoride diethyl etherate (BFEE) solution is a middle strong Lewis acid. It is also a better electrolyte for the electrosyntheses of high quality conducting polymers from various aromatic monomers, such as thiophene, benzene and their derivatives. This dissertation focused on the electrosyntheses of high-quality conducting polymers from thiphene in pure BFEE and mixed electrolytes of BFEE and acetonitrile, and the electrosyntheses of flurene in the same system. And the copolymer of thiphene and flurene is electropolymerized. The properties of the polymers and the copolymer are also investigated.1.The polythiophene (PT) films are polymerized in the the BFEE solution which have a lower oxidation potential of 1.35V (vis SCE). And thiophene monomer has a lower oxidation potential in the system comparing to the traditional solvent and electrolyte. It can been explained by that the BFEE may exist as a polar molecule [(C2H5)O+]BF4-, which supports the conducting medium(dopant).2.The polyflurene (PF) films are polymerized directly from BFEE solution, which contain different amounts of acetonitrile. The larger the concentrations of BFEE (by volume) in acetonitrile are, the lower the oxidation potential is, showing a strong solvent effect in this system. The cyclic voltammery (CV) of PF shows perfect redoxic property in the pure electrolytes. Fluorescent spectral studies indicate that PF...