Intermetallic junction contribution to the CO electrooxidation on a Pt/Au electrode: the excess voltammetric current

Abstract

The contribution of the intermetallic junction to the electrocatalytic activity of a Pt/Au electrode for the carbon monoxide oxidation reaction (COOR) in alkaline solution is evaluated on the basis of the excess voltammetric current. This contribution is measured on a new type of bimetallic electrode characterized by a large ratio between the total intermetallic perimeter and the electrode area. The results obtained demonstrate that Pt/Au heterojunction enhances the reaction rate in two potential regions. This improvement is explained on the basis of the spillover of the CO adatoms from one side of the intermetallic junction to the other.