The Effect of Concentration on the Galvanostatic Pulse Deposition of PtRu

摘要

Fabrication of PtRu nanoparticles was conducted by a galvanostatic pulse electrodeposition technique. We studied various deposition parameters including current on-time and off-time, current density, as well as concentrations for the Pt and Ru precursors in the plating bath in order to determine the optimized process condition for the highest methanol oxidation ability. Cyclic voltammetric profiles were obtained in electrolytes of 0.5 M H_2SO_4, and mixture of 0.5 M H_2SO_4 and 1.0 M CH_3OH to determine characteristics in the hydrogen absorption/desorption and peak currents in the anodic/cathodic scans. We observed that a shorter current off-time resulted in better catalytic abilities when the Pt precursor concentration was increased. Partial dissolution of Ru in the as-deposited PtRu nanoparticles during the current off-time might be responsible.