Popis: |
The electrocatalytic activity of several types of polypyrrole films bearing cationic pendant group [tris(bipyridyl)ruthenium(II) complexes, viologen, ammonium] and containing dispersed microparticles of RuO2 towards the oxidation of alcohols to aldehydes or ketones has been investigated. Best results are obtained with polypyrrole films substituted by a tris(bipyridyl)ruthenium(II) complex, the latter acting as an electron relay for the electrogeneration of the strong oxidizing species RuO42−. The influence of several parameters such as base, supporting electrolyte, electrolysis potential and catalyst amount on the efficiency of the electrocatalysis has been examined. Under optimum conditions a maximum turnover of 10 900 was reached. In all cases the lifetime of these electrode materials was limited by the slow release of the RuO42− species. |