Fe(111)-Mediated Electrooxidation of Pyridine and Several Derivatives to Produce a Novel n-Dopable Conducting Polymer

摘要

Pyridine and lutidine can be oxidatively electropolymerized in the presence of Fe(II) salts to give films of anew, n-dopable conducting polymer. Substoichiometric amounts of the Fe(II) salts are required to achieve efficient polymerization, implying that the metal is acting in a catalytic capacity in its oxidized form, this new material exhibits strong absorbance at wavelengths shorter than ca. 400 am. The material can be reversibly reduced over the range 0 to -0.8 V vs Ag/AgCl. Reduction leads to a decrease in the intensity of the short wavelength uv-vis band and appearance of a broad, long wavelength band in the 800-900 run range, indicative of an n-doping process to produce a conductive material with low bandgap. These spectral changes are shown to be completely reversible. The potential dependence of the conductivity of the material is tested by examining the effectiveness of the film as an electrode material using a solution phase compound with two redox couples at potentials within and outside of the conducting region for the material. Both the oxidized and reduced forms of the polymer are insoluble in common organic solvents (e.g., methanol, acetone, chloroform, and DMSO).