Structure effects on the energetics of the electrochemical reduction of CO2 by copper surfaces

► CO2 electrochemical reduction to hydrocarbons on Cu. ► DFT study of the elementary energetics on fcc Cu (111), (100), and (211) facets. ► Greatest stabilization of CHO vs CO on (211) facet. ► Lowest overall potential requirement on (211) facet. ► Change in potential-limiting step between (111) and (211) facets.