Progress in regulating the electrocatalytic CO₂ reduction performance through the synergistic effect of Cu-based bimetallics

As an effective way to implement net-zero CO₂ emissions and storage of intermittent renewable energy, the reduction of CO₂ into chemical fuels through the electrochemical method has attracted considerable interest. Monometallic copper (Cu) has shown great potential in transforming CO₂ to CO and hydrocarbon compounds, especially multi-carbon products; however, its low product selectivity limits its application. Alternatively, Cu-based bimetallic electrocatalysts have shown particular capacity to favor the desired products because they theoretically provide a platform for modulating the binding affinity of key intermediates. This review focuses on the recent advances in Cu-based bimetallic electrocatalysts, including the reaction mechanism of electrocatalytic CO₂ reduction using specific catalytic systems, methods for the fabrication of Cu-based bimetallic catalysts, and categories of bimetallic Cu-based catalysts with different secondary metals. Finally, we propose the challenges and prospects for Cu-based bimetallic catalysts for electrochemical CO₂ conversion. The purpose of this review is to categorize the ideas in the design and synthesis of bimetallic catalysts, thus providing a valuable reference for improving the CO₂ reduction ability by constructing bimetallic catalysts.