Improved electrochemical conversion of CO₂ to multicarbon products by using molecular doping

Area of Science:

• Electrochemistry
• Catalysis
• Materials Science

Background:

• Electrochemical reduction of carbon dioxide (CO2) is key for a circular carbon economy.
• Developing efficient catalysts for CO2 conversion into multicarbon products is a significant challenge.

Purpose of the Study:

• To enhance CO2 conversion into hydrocarbon molecules using modified bimetallic silver-copper catalysts.
• To investigate the role of aromatic heterocycles in directing the reaction pathway and improving catalytic performance.

Main Methods:

• Modification of bimetallic silver-copper catalyst surfaces with thiadiazole and triazole derivatives.
• Utilizing operando Raman and X-ray absorption spectroscopy to study catalyst behavior.
• Conducting electrocatalytic measurements and analyzing reaction products.

Main Results:

• Aromatic heterocycles on the catalyst surface promote the formation of C2+ products (ethanol and ethylene).
• Electron-withdrawing functional groups tune the electronic state of copper, enhancing reaction rates.
• Achieved high Faradaic efficiency (≈80%) for C2+ products and 20.3% full-cell energy efficiency.

Conclusions:

• Surface modification of bimetallic catalysts with aromatic heterocycles is an effective strategy for selective CO2 electroreduction.
• The electronic modulation of copper sites by heterocycles is crucial for high C2+ product selectivity and efficiency.
• This approach offers a promising pathway for sustainable carbon utilization and a circular carbon economy.