Influence of water on the anodic oxidation mechanism of diethylenetriamine (DETA) on platinum electrode

Diethylenetriamine was oxidised in different electrolytes on platinum electrode. In non-aqueous electrolyte, an irreversible oxidation peak characteristic of DETA oxidation appears on the voltammogram followed by a constant current until the higher limit of the sweeping potential domain is attained. The following successive scans showed a high decrease of the cur-rent intensity and that is due to the formation of an insulating coating layer on the electrode surface. When water is added to the non-aqueous electrolyte, a DETA oxidation wave appears on the voltammograms. That oxidation wave is observed on the following scans. Indeed, DETA oxidation mechanism seems to be different either the electrolyte is free or not of water. In non-aqueous electrolyte, DETA oxidation leads to electrode surface covering by a thin polymeric film but in water containing electrolyte, oxygen evolution occurs and DETA oxidation leads to uncoated surface by producing aldehyde and amine through imine hydrolysis.