Optimizing copper nanoparticles with a carbon shell for enhanced electrochemical CO₂ reduction to ethanol

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Electrochemical reduction of carbon dioxide (CO2RR) is crucial for sustainable energy and climate change mitigation.
• Developing stable electrocatalysts that selectively produce desired products remains a significant challenge.

Purpose of the Study:

• To develop a carbon shell coating strategy to enhance the stability and selectivity of copper-based electrocatalysts for CO2RR.
• To investigate the role of the carbon shell in preventing catalyst reconstruction and promoting ethanol production.

Main Methods:

• Synthesized carbon shell-coated copper electrocatalysts (Cu-x-y) using a copper-based metal-organic framework precursor.
• Employed calcination in various atmospheres (N2, H2, NH3) at different temperatures.
• Conducted electrochemical performance tests and theoretical calculations.

Main Results:

• Carbon shell-coated catalysts achieved a faradaic efficiency of ~67.8% for ethanol production.
• The catalysts demonstrated stable operation for over 16 hours, outperforming uncoated counterparts.
• Control experiments and calculations confirmed the stabilizing effect of the carbon shell and Cu-C bonds.

Conclusions:

• The carbon shell coating effectively protects electrocatalysts from reconstruction during CO2RR.
• This strategy tunes the electronic environment of copper, promoting CO* intermediate formation and coupling for enhanced ethanol selectivity.
• The proposed method offers a valuable approach for designing robust and efficient electrocatalysts for CO2 conversion.