Structure - reactivity relationships: the oxidation of aliphatic amines on the gold electrode

The electrooxidation of isomeric butylamines at a gold electrode in contact with an alkaline electrolyte solution was studied by cyclic voltammetry. Differences in the electrochemical activity of the isomers were found. It was ascertained that the amine oxidation is catalysed by the gold oxide layer. Substrate molecules are adsorbed on the gold electrode surface in the potential range preceding the oxidation. The adsorptive behaviour of the substrate molecules was evaluated on the basis of changes in the differential capacitance of the double layer at the electrode/solution interface.