Tuning catalyst-support interactions enable steering of electrochemical CO₂ reduction pathways

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Catalyst-support interactions are crucial for controlling catalytic activity.
• Rational design of catalyst supports is hindered by unclear property-activity relationships.
• Electrochemical carbon dioxide reduction (CO2RR) is a key process for sustainable chemical production.

Purpose of the Study:

• To investigate the influence of support electronegativity on reaction pathways in CO2RR.
• To establish a clear property-activity relationship for catalyst support design.
• To develop highly selective and stable catalysts for CO2RR.

Main Methods:

• Fabrication of a model system using copper (Cu) nanoparticles on carbon supports with varying heteroatom dopants.
• Systematic variation of dopant electronegativity to tune catalyst-support interactions.
• Electrochemical characterization, including Faradaic efficiency (FE) measurements at controlled current densities.
• Long-term stability testing and performance evaluation using simulated flue gas.

Main Results:

• Support electronegativity directly influences electron density on Cu nanoparticles and CO2RR pathways.
• High electronegativity dopants promote selectivity towards multicarbon products (C2+).
• A composite Cu and fluorine-doped carbon catalyst achieved 82.5% C2+ FE at 400 mA cm-2 with 44-hour stability.
• The developed catalyst demonstrated a 5.3-fold increase in C2+ FE using simulated flue gas compared to a reference Cu catalyst.

Conclusions:

• Electronegativity is a critical parameter for tuning catalyst-support interactions in CO2RR.
• This work provides a rational design principle for developing advanced CO2RR catalysts.
• The developed F-doped carbon supported Cu catalyst shows significant potential for efficient and selective CO2 conversion.