Co-catalytic effect of nickel in Pt-Ru/C and Pt-Sn/C electrocatalysts for ethanol electrooxidation

-In the present study, we examined the effect of adding nickel to Pt-Ru and Pt-Sn catalysts for ethanol electrooxidation. The alcohol-reduction process with ethylene glycol was used to prepare ten electrocatalysts. These were microchemically and physically characterized by EDX and XRD analysis. The electrocatalysts were evaluated at minielectrodes with cyclic voltammetry at 25 and 50 °C in sulfuric acid and ethanol solutions, and as anodes in fuel cell tests. Nickel addition to Pt-Ru mixtures significantly increased the catalytic activity toward ethanol electrooxidation. For Pt-Ru-Ni catalysts, the current density was around five times greater than all other investigated mixtures. Nickel also duplicated the catalytic activity of the Pt-Sn catalyst. Furthermore ethanol electrooxidation increased with temperature for most catalytic mixtures, and the electrocatalytic activity of mixtures containing nickel, demonstrate a considerable increase with temperature. Pt-Ru-Ni catalytic activity was higher than that of all other investigated mixtures. The fuel cell test demonstrated that the addition of nickel to Pt-Ru and Pt-Sn catalysts enhances the performance of the DEFC. Keywords-Ethanol; Electrooxidation; PtRuNi; PtSnNi; Fuel cell.