In Situ Surface-Enhanced Raman Spectroscopy of CO₂ Reduction by Metal-Organic Framework-Derived Copper Electrode

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrochemical CO2 reduction (CO2RR) is crucial for sustainable carbon utilization.
• Developing efficient and selective catalysts for CO2RR remains a significant challenge.
• Metal-Organic Frameworks (MOFs) offer tunable structures for catalyst design.

Purpose of the Study:

• To synthesize and characterize a novel Cu-MOF-derived catalyst for electrocatalytic CO2RR.
• To investigate the catalytic performance and reaction mechanisms using in situ techniques.
• To understand how catalyst structure and copper valence state influence CO2RR selectivity.

Main Methods:

• Pyrolysis of Cu-based MOFs to create Cu0/Cu+1/C/N catalyst with porous carbon coating.
• In situ Raman and Surface-Enhanced Raman Spectroscopy (SERS) for real-time reaction monitoring.
• Electrochemical measurements to assess catalytic performance and selectivity.

Main Results:

• The Cu-MOF-derived catalyst demonstrated enhanced selectivity towards C2 products (e.g., ethylene, ethanol).
• Porous carbon coating stabilized the catalyst, inhibiting hydrogen evolution and maintaining copper valence states.
• In situ spectroscopy revealed dynamic evolution of key intermediates (*CO, *CHO) and ion adsorption.

Conclusions:

• Cu-MOF-derived catalysts are promising for selective electrochemical CO2 reduction.
• Tuning copper valence states and active site structure is key to improving C2 product selectivity.
• In situ spectroscopic insights provide a deeper understanding of CO2RR pathways on the catalyst surface.