Significant activity improvement of Au/C by Pt deposition for electrooxidation of ethanol

Abstract

The electrochemical deposition of Pt on Au nanoparticles loaded on carbon black and coated on glassy carbon (GC) electrode and the electrocatalytic oxidation of ethanol on Pt-modified Au/C catalysts are investigated. Structure analysis shows a uniform distribution of the metal nanoparticles on carbon black and a partial coverage of the Au surface by the deposited Pt. Cyclic voltammetric (CV) results display that the deposition of a small amount of Pt significantly improves the activity of the Au/C catalyst for ethanol oxidation in alkaline solution in terms of oxidation potential and current density. For example, the peak on the Pt-modified Au/C catalyst with a Pt:Au atomic ratio of 1:463 shows the onset oxidation potential close to that on Pt/C catalyst but the peak current density several times higher than that on Au/C and Pt/C catalysts. In the wide range of Pt loadings the Pt-modified Au/C catalysts exhibit considerably higher activity than Au/C and Pt/C catalysts. The modification of Au/C with Pt is found to be very effective for improving the activity of the Au/C catalyst towards ethanol oxidation.