Size effects of supported Cu-based catalysts for the electrocatalytic CO₂ reduction reaction

The electrocatalytic CO₂ reduction reaction (CO₂RR) is a promising method to convert CO₂ into valuable chemical raw materials. Cu-based catalysts have been widely considered as “star” materials that can reduce CO₂ to hydrocarbon and C₂₊ products. Naked Cu has the disadvantages of poor selectivity and low stability. However, supported Cu-based catalysts show excellent catalytic performance due to the interaction between Cu-based metals and supports. There are apparent differences in the interaction between Cu species of different sizes and supports, affecting selectivity. We discussed the supported Cu-based catalysts based on the effect of size on performance. This paper first summarized the mechanism of the CO₂RR. Then, the size effects of supported Cu-based single atoms, diatoms, clusters and nanoparticles on the catalytic activity and selectivity for the CO₂RR were emphatically discussed and reviewed. Finally, this paper presented challenges and expectations for the design and selection of catalysts.