Enhancing C2–C3 Production from CO2 on Copper Electrocatalysts via a Potential-Dependent Mesostructure

The electrochemical conversion of CO2 to hydrocarbons and alcohols for use as a renewable energy storage medium is a promising approach to CO2 utilization and energy sustainability. Herein, we demonstrate that the selectivity of an electrochemically reduced Cu(OH)2 nanowire catalyst toward C2–C3 compounds (ethylene, ethanol, and n-propanol) is systemically modified by surface morphology, which is governed by the electrolysis potential. The total Faradaic efficiency of CO2 reduction to C2–C3 compounds is found to be 38% at a moderate potential of −0.81 V vs RHE, and stable electrocatalytic performance is observed for 40 h of CO2 electrolysis. Electro- and physicochemical analyses indicate that the Cu(OH)2 nanowires are completely reduced to metallic Cu, forming a mesostructured catalyst after a few minutes of electrolysis. The shift in product selectivity is strongly correlated with this change in mesoscale catalyst morphology, offering additional dimensionality and multiple length scales for catalyst desi...