Catalyst design for the electrochemical reduction of carbon dioxide: from copper nanoparticles to copper single atoms

Carbon dioxide reduction reaction (CO₂RR) is an efficacious method to mitigate carbon emissions and simultaneously convert CO₂ into high-value carbon products. The efficiency of CO₂RR depends on the development of highly active and selective catalysts. Copper (Cu)-based catalysts can effectively reduce CO₂ to hydrocarbons and oxygen-containing compounds because of their unique geometric and electronic structures. Most importantly, Cu can reduce CO₂ to multiple carbon products (C₂₊). Therefore, this review aims to outline recent research progress in Cu-based catalysts for CO₂RR. After introducing the mechanism of this electroreduction reaction, we summarize the influence of the size, morphology, and coordination environment of single component Cu-based catalysts on their performance, especially the performance control of catalysts that contain nano Cu or Cu single-atom sites. Then, the synergistic regulation strategies of doping other metals into Cu-based catalysts are summarized. Finally, the research on the supports used for Cu-based catalysts is reviewed. The prospects and challenges of Cu-based catalysts are discussed.