Reactions and Mechanism of the Electrochemical Reduction of Carbon Dioxide at Alloyed Copper-Silver Electrodes

Abstract

The electrochemical reduction of carbon dioxide on electrodes made of a copper-silver alloy in aqueous solutions was investigated, and the results were compared with those at a pure copper electrode, which is known to produce hydrocarbons such as methane and ethylene at high current efficiencies. The electrode of a Cu-Ag alloy of nearly 2:3 atomic ratio gave a higher current efficiency for ethylene and a lower current efficiency for methane than those at a Cu electrode. The reaction mechanisms of CO2 reduction on Cu, Ag and alloyed Cu-Ag electrodes were discussed in relation with their electronic structures.