Voltammetric investigation of nickel-platinum codeposits for methanol oxidation in KOH solutions

The electrochemical and electrocatalytic properties of Ni-Pt codeposits for methanol oxidation in an alkaline medium were characterized by cyclic volt ammetry. The Ni-Pt codeposit with ca. Pt 60 a/o was found to exhibit the ma ximal activity for the oxidation of methanol in the low potential range. Th e electrocatalytic activity of all Ni-Pt codeposits (before and after leach ing) for methanol oxidation was found to depend on their original compositi ons/textural properties before leaching. The hydroxyl Pt(IV) species with a higher hydrated property possessed a higher activity for the methanol oxid ation and oxygen evolution reactions (OER). The presence of a hydroxyplatin um intermediate, Pt(OH)(ads), was proposed to be responsible for the anodic peaks of methanol oxidation in the less positive potential region on both positive and negative sweeps.