Hydroxylation boosted low-overpotential CO₂ reduction to ethylene for a Cu/PTFE electrode

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Carbon dioxide (CO2) reduction is crucial for sustainable energy and chemical production.
• Developing efficient electrocatalysts for CO2 reduction to valuable hydrocarbons remains a significant challenge.
• Ethylene production via CO2 electroreduction offers a pathway to renewable feedstocks.

Purpose of the Study:

• To develop a highly efficient electrode for CO2 reduction reaction (CO2RR).
• To investigate the role of hydroxyl (*OH) groups in facilitating CO2 activation and C-C coupling.
• To achieve high selectivity and efficiency for ethylene production at low overpotentials.

Main Methods:

• Fabrication of a copper/polytetrafluoroethylene (Cu/PTFE) composite electrode.
• Electrochemical characterization of the electrode for CO2 reduction.
• Analysis of reaction products and faradaic efficiency (FE) using techniques like gas chromatography.
• In situ/operando studies to probe the role of *OH species.

Main Results:

• The Cu/PTFE electrode demonstrated high *OH coverage, promoting CO2 activation and C-C coupling.
• Achieved a faradaic efficiency for ethylene exceeding 50% at -246 mV vs. RHE.
• The maximum FE for carbon products reached 60.3%.
• The electrode exhibited enhanced performance compared to conventional Cu-based catalysts.

Conclusions:

• The Cu/PTFE electrode is a promising material for efficient and selective CO2 electroreduction to ethylene.
• High *OH coverage is key to enhancing both CO2 activation and C-C coupling.
• The low operating potential signifies energy efficiency for industrial applications.