Ethanol Oxidation on Pd/Au(111) Bimetallic Surfaces in Alkaline Solution

Abstract

Catalytic properties of Pd/Au(111) nanostructures obtained by spontaneous palladium deposition using PdSO4 and PdCl2 salts were examined for the oxidation of ethanol in alkaline media. Atomic force microscopy has shown that counter anions in Pd salts are responsible for the differences in surface topography. In both cases the oxidation of ethanol is characterized by the rise of a new peak at approximately the same potential for the same coverage, indicating similar electronic modification of Pd islands by the Au(111) substrate. Pd/Au(111) nanostructures obtained using PdCl2 salt have shown higher ethanol oxidation current densities, which can be ascribed to the surface structure consisting of thinner and smoother Pd deposit providing more convenient sites for the adsorption of ethanol and its subsequent oxidation.