Modification with platinum of silver-deposited nickel wire electrodes for electrocatalytic oxidation of alcohols

Abstract

A silver-deposited nickel (Ag/Ni) wire electrode was prepared via a galvanic replacement reaction between Ag⁺ and Ni wire in aqueous solution. It was then found that the Ag/Ni wire electrode could be modified with Pt simply by treating it in an aqueous solution of K₂PtCl₄. Although the deposition of Ag on Ni wire was limited in amount, forming Ag deposits less than 100 nm in size, a considerable increase in the electrocatalytic currents for the oxidation of alcohols could be observed after further modification of the Ag/Ni wire electrodes with Pt. This is in contrast to the fact that it was difficult to produce sufficient electrocatalytic response by modifying Ni wire with Pt directly via a simple galvanic replacement between PtCl₄²⁻ and Ni wire. Thus, the prior deposition of Ag was found to strongly promote modification with Pt via a simple stepwise treatment using AgNO₃ and K₂PtCl₄. This approach should be effective in modifying various Ni materials with Pt, including Ni microparticles.