Polymer Modification Strategy to Modulate Reaction Microenvironment for Enhanced CO₂ Electroreduction to Ethylene.

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Electrocatalytic carbon dioxide reduction (eCO2 RR) is crucial for sustainable energy solutions.
• Improving CO2 solubility and reaction kinetics at the electrode-electrolyte interface is key to high efficiency.
• Controlling the electrode surface microenvironment is an effective strategy to enhance eCO2 RR.

Purpose of the Study:

• To develop a simple and efficient method for structuring electrocatalysts with a superhydrophobic surface microenvironment.
• To improve the selectivity and efficiency of electrocatalytic carbon dioxide reduction.
• To investigate the role of polytetrafluoroethylene (PTFE) in modifying the electrode surface for enhanced eCO2 RR.

Main Methods:

• One-step co-electrodeposition of copper (Cu) and polytetrafluoroethylene (PTFE) on carbon paper.
• Fabrication of a superhydrophobic Cu-based electrode.
• Electrocatalytic performance evaluation in an H-type cell, measuring Faraday efficiency (FE) and selectivity.

Main Results:

• The superhydrophobic Cu-PTFE electrode achieved high ethylene (C2H4) selectivity with a Faraday efficiency (FE) of 67.3% at -1.25 V vs. RHE.
• Ethylene selectivity was 2.5 times higher compared to a regular Cu electrode without PTFE.
• PTFE acted as a surface modifier, enhancing eCO2 RR activity and inhibiting water (proton) adsorption.

Conclusions:

• The developed superhydrophobic surface strategy effectively modulates the electrode microenvironment for improved eCO2 RR.
• This approach offers a promising pathway for enhancing gas-conversion electrocatalysts.
• The Cu-PTFE electrode demonstrates significant potential for efficient CO2 conversion to valuable products like ethylene.