Investigation of nanometals (Ni and Sn) in platinum-based ternary electrocatalysts for ethanol electro-oxidation in membraneless fuel cells

Abstract

In the present work, Carbon supported Pt100, Pt80Sn20, Pt80Ni20and Pt80Sn10Ni10 electrocatalysts with different atomic ratios were prepared by ethylene glycol-reduction method to study the electro-oxidation of ethanol in membraneless fuel cell. The electrocatalysts were characterized in terms of structure, morphology and composition by using XRD, TEM and EDX techniques. Transmission electron microscopy measurements revealed a decrease in the mean particle size of the catalysts for the ternary compositions. The electrocatalytic activities of Pt100/C, Pt80Sn20/C, Pt80Ni20/C and Pt80Sn10Ni10/C catalysts for ethanol oxidation in an acid medium were investigated by cyclic voltammetry (CV) and chronoamperometry (CA). The electrochemical results showed that addition of Ni to Pt/C and Pt–Sn/C catalysts significantly shifted the onset of ethanol and CO oxidations toward lower potentials. The single membraneless ethanol fuel cell performances of the Pt80Sn10Ni10/ C, Pt80Sn20/C and Pt80Ni20/C anode catalysts were evaluated at room temperature. Among the catalysts investigated, the power density obtained for Pt80Sn10Ni10/C (37.77 mW/cm2) catalyst was higher than that of Pt80Sn20/C (22.89 mW/cm2) and Pt80Ni20/C (16.77 mW/ cm2), using 1.0 M ethanol + 0.5 M H2SO4 as anode feed and 0.1 M sodium percarbonate + 0.5M H2SO4 as cathode feed.