Synergistic Effect of Cu₂O Mesh Pattern on High‐Facet Cu Surface for Selective CO₂ Electroreduction to Ethanol

Abstract Although the electroconversion of carbon dioxide (CO₂) into ethanol is considered to be one of the most promising ways of using CO₂, the ethanol selectivity is less than 50% because of difficulties in designing an optimal catalyst that arise from the complicated pathways for the electroreduction of CO₂ to ethanol. Several approaches including the fabrication of oxide‐derived structures, atomic surface control, and the Cu⁺/Cu interfaces have been primarily used to produce ethanol from CO₂. Here, a combined structure with Cu⁺ and high‐facets as electrocatalysts is constructed by creating high‐facets of wrinkled Cu surrounded by Cu₂O mesh patterns. Using chemical vapor deposition graphene growth procedures, the insufficiently grown graphene is used as an oxidation‐masking material, and the high‐facet wrinkled Cu is simultaneously generated during the graphene growth synthesis. The resulting electrocatalyst shows an ethanol selectivity of 43% at −0.8 V versus reversible hydrogen electrode, which is one of the highest ethanol selectivity values reported thus far. This is attributed to the role of Cu⁺ in enhancing CO binding strength, and the high‐facets, which favor C–C coupling and the ethanol pathway. This method for generating the combined structure can be widely applicable not only for electrochemical catalysts but also in various fields.