In situ copper faceting enables efficient CO₂/CO electrolysis.

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Copper-catalyzed electrochemical reduction of carbon dioxide (CO2) is a promising route for synthesizing multicarbon (C2+) products.
• The thermodynamically stable Cu(111) surface favors single-carbon production, limiting energy efficiency and C2+ yields.

Purpose of the Study:

• To engineer a copper catalyst that preferentially exposes Cu(100) facets for enhanced C2+ product synthesis.
• To improve the energy efficiency and production rates of electrochemical CO2 reduction.

Main Methods:

• In situ copper faceting induced by electrochemical reduction.
• Utilizing a phosphate ligand to control precatalyst evolution, CO generation, and surface reconstruction to Cu(100).

Main Results:

• The engineered Cu(100) catalyst achieved current densities over 500 mA cm-2 and Faradaic efficiencies exceeding 83% for C2+ products from both CO2 and CO reduction.
• Sustained performance over 150 hours at 500 mA cm-2, maintaining 37% full-cell energy efficiency and 95% single-pass carbon efficiency.

Conclusions:

• Electrochemical reduction can be used to create copper catalysts with preferential Cu(100) facet exposure.
• This approach significantly enhances the efficiency and selectivity of multicarbon product formation from CO2 and CO electroreduction.