Scaling preparation of CuO for efficient electrochemical reduction of CO2 to C2+ products

The conversion of CO2 to C2+ products, especially by electrochemical carbon dioxide reduction (ECR), is a promising strategy for the utilization of CO2 and the effective mitigation of the energy crisis and global warming. The development of industrially available catalysts is key to achieving this conversion. In this work, we prepared several CuO catalysts using the ball milling method and evaluated their performance in ECR using an H-type electrolytic cell. Different Cu elemental contents as well as calcination temperatures significantly altered the crystallinity and crystalline phase species of the formed crystals. Among the prepared catalysts, CuO-30 %-350 could achieve 50 % faradaic efficiency of C2+ products (FEC2+) at 20 h of stable operation. Characterization results showed that CuO particles were loaded on the SiO2 surface, and CuO-30 %-350 possessed a large electrochemically active specific surface area, fast electron transport rate, and low kinetic barriers, which was the reason for its high FEC2+. This study provides a green and efficient idea for the large-scale preparation of ECR catalysts.