Nickel and nickel-based nanomaterials are an attractive choice to replace noble metals as electrocatalyst in alkaline direct alcohol fuel cells (DAFCs) owing to their lower cost and suitable electrocatalytic activity. Among the different synthetic methods available for the production of nanostructured materials, galvanostatic electrodeposition offers a fast and simple means of fabricating active electrodes. Therefore, thin-layers of nickel were electrodeposited onto polycrystalline gold electrodes using constant current pulses from an electrolyte containing 50 mM NiSO4. The electrocatalytic properties of the nickel nanostructures in alkaline medium, in which the catalytic species NiOOH is formed, were evaluated through cyclic voltammetry in 0.5 M methanol + 1 M KOH. The effects of current density pulse and the presence of sulfate or chloride anions in the supporting electrolyte on the electrocatalytic activity of the deposits were studied using Ni(OH)2 surface concentration, Gamma, and electrocatalytic intensity, EI, as performance parameters. It was found that highest electrolcatalytic activities were obtained when using current densities pulses close to 4.0 mA/cm2 in the presence of sulfates. It was found that the presence of sulfates leads to a strong correlation between the electrocatalytic activity for the oxidation of methanol and the surface concentration of Ni(OH)2.
A Novel Synthesis of triangular Pt Nanosheets on Pd surface with a Strong Electrocatalytic Activity for Oxidation of Methanol