Study of electrocatalytic oxidation of ethanol on Ni modified graphite electrode in NaOH solution

At present, the ever‐increasing use of energy, and especially of fossil fuels, is a major source of air pollution. As a result of large energy consumption and global ecological awareness, direct alkaline ethanol fuel cell (DAEFC) has gained a lot of attention as an alternative to fossil fuel combustion since it satisfies critical criteria such as; fuel transportation, easiness of ethanol production, efficiency, safety, compatibility, and cost. A considerable number of studies, have been devoted to the electrocatalytic oxidation of ethanol, which is of paramount importance in the development of DAEFCs. In the present study, we investigated the activity of a modified Ni‐based graphite electrode (G/Ni) and the effects on the electrocatalytic oxidation of ethanol in a NaOH solution (0.1mol/L). The catalysts were prepared by cycling the graphite electrode in solution containing Ni ion at cathodic potentials. The methods of cyclic voltammetry (CV) and chronoamperometry (CA) were employed. The result showed that, in the presence of ethanol, the modified Ni‐based graphite electrode (G/Ni) exhibited a significantly higher response for ethanol oxidation while in the absence of ethanol, the graphite electrode presents no activity. More specifically, the growth of the anodic peak is considerable and the negligible cathodic peak in the presence of methanol is attributed to an irreversible oxidation process. It can be seen that the anodic peak current density increases with increasing methanol concentration. The peak current of the oxidation of nickel hydroxide increase is followed by a decrease in the corresponding cathodic current in presence of ethanol.