Electrochemical Reduction of Carbon Dioxide on Single-Crystal Copper Membrane

Abstract

The selective electrochemical reduction of carbon dioxide (CO 2 ) was demonstrated over single-crystal copper membranes. The crystalline copper membranes were deposited on specific support substrates that were c-plane sapphire for Cu(111), MgO(100) for Cu(100), and MgO(110) for Cu(110). Methane (CH 4 ) and ethylene (C 2 H 4 ) formation in CO 2 electrochemical reduction was more favorable on Cu(111) membranes than that on polycrystalline copper plates. The electrolyte type that CO 2 gas was effectively dissolved in, was important to significantly maintain electrochemical activity. The product selectivity for CO 2 conversion was strongly dependent on the crystal structure of the copper surface.