1Electroanalytical Chemistry Laboratory, Department of Chemistry, Faculty of Sciences, Azarbaijan Shahid Madani University, Tabriz 53714-161, Iran
2Electroanalytical Chemistry Laboratory, Department of Chemistry, Faculty of Sciences, Azarbaijan Shahid Madani University, Tabriz, Iran.
In this study, the electrocatalytic activity of the Co@Pt core-shell nanoparticles toward the ethanol oxidation reaction has been investigated by cyclic voltammetry and chronoamperometry in acidic and alkaline media in details. The physicochemical data obtained in alkaline solution are compared to those in acidic solution. The obtained results demonstrate that while in the both media Co@Pt core-shell nanoparticles exhibit a good electrocatalytic performance for ethanol oxidation reaction; in alkaline medium the Co@Pt core-shell catalyst presents more catalytic activity (1.4 times), exchange current densities (about 8 times), electrochemical active surface area (1.2 times) and stability (about 2 times). The effect of some experimental factors such as electrolytes (H2SO4 and NaOH) and ethanol concentrations was studied and optimum conditions were suggested. From these points, we conclude that ethanol oxidation reaction can be improved with an alkaline electrolyte and the oxidation reaction is highly dependent on the pH of electrolyte. These results indicate that the system studied in the present work; Co@Pt core-shell nanoparticles on the carbon-ceramic electrode, is the most promising system for use in alkaline fuel cells.
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