Voltage- and pH-driven evolution of multi-pathway C-C coupling in CO₂ electroreduction on copper

Area of Science:

• Electrochemistry
• Catalysis
• Computational Chemistry

Background:

• Reducing carbon dioxide (CO2) to multi-carbon products is vital for climate and energy solutions.
• Copper is the only known catalyst for this electrochemical CO2 reduction reaction (CO2RR).
• Existing models of C-C coupling mechanisms on copper are incomplete, lacking dynamic and system-wide perspectives.

Purpose of the Study:

• To investigate the influence of environmental factors on multi-pathway C-C coupling mechanisms in CO2 reduction.
• To provide a dynamic and comprehensive understanding of C-C coupling on copper surfaces.

Main Methods:

• Utilized microkinetic modeling to systematically study C-C coupling pathways.
• Analyzed the effects of varying electrochemical conditions, specifically voltage and pH.

Main Results:

• Demonstrated that voltage and pH dynamically regulate multiple C-C coupling routes, rather than enhancing a single step.
• Observed competition among different coupling pathways under varying conditions.
• Findings align with previous experimental observations in CO2RR.

Conclusions:

• Developed a more comprehensive understanding of C-C coupling mechanisms in CO2 reduction under realistic electrochemical conditions.
• Provides new insights for the rational design and optimization of copper-based catalysts for sustainable multi-carbon product synthesis.