Preparation of Pd-Modified Ni Foam Electrodes and Their Use as Anodes for the Oxidation of Alcohols in Basic Media

Pd-modified Ni foam electrodes were prepared by a spontaneous deposition method. Ni foam samples were immersed in acid PdCl2solutions for different durations (tSD). The Pd loading and the surface area of the Pd deposits were determined as a function of [PdCl2] and tSD. SEM-EDX showed that Pd deposits were homogeneously formed on the walls of both the outer and the inner cells of the Ni foam. Pd-modified Ni foam electrodes were used as anodes for the oxidation of methanol, ethanol, ethylene glycol, and glycerol in basic media. Voltammetric curves for the oxidation of alcohols showed that the peak current increased with increasing Pd loading in a sub-linear way. For the lowest loading explored (ca. 1 mg of Pd in a 1 cm3foam volume), the peak current per unit Pd mass was of the order of 650 A g-1for 0. 5 M methanol and ethanol, ca. 1,500 A g-1for glycerol and higher than 2,000 A g-1for ethylene glycol. © 2011 Springer Science+Business Media, LLC