Recent Advances in CO₂ Reduction Electrocatalysis on Copper

Electroreduction of CO2 represents a promising approach toward artificial carbon recycling for addressing global challenges in energy and sustainability. The foreground of this approach is dependent on the development of efficient electrocatalysts capable of selectively reducing CO2 to valuable (oxygenated) hydrocarbon products at low overpotentials. Here, we present an overview of the recent developments of Cu electrocatalysts for CO2 reduction. Our focus is placed on elucidation of the structure–property relationships of monometallic Cu electrocatalysts, which is believed to be the foundation for understanding alloys and other more complex catalytic systems. Reported mechanisms are discussed in terms of grain boundaries, open facets, residual oxides, subsurface oxygen, local pH effect, etc. After this discussion, remaining questions are raised for further development of advanced electrocatalysts for energy and chemically efficient CO2 reduction.