Selective CO2 reduction on a polycrystalline Ag electrode enhanced by anodization treatment

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Electrochemical reduction of carbon dioxide (CO2) is a key technology for sustainable energy and chemical production.
• Silver (Ag) is a promising catalyst for CO2 reduction, but its efficiency and selectivity need improvement.

Purpose of the Study:

• To enhance the performance of polycrystalline silver (Ag) for electrochemical CO2 reduction to CO.
• To investigate the effects of a simple anodization treatment on Ag catalyst properties and performance.

Main Methods:

• Polycrystalline silver (Ag) electrodes were subjected to a simple anodization treatment.
• Electrochemical reduction of CO2 was performed in an aqueous electrolyte.
• Product selectivity and efficiency were analyzed using Faradaic efficiency measurements.

Main Results:

• The anodization treatment significantly improved the electrochemical reduction of CO2 to CO on Ag.
• A high CO faradaic efficiency of 92.8% was achieved at an overpotential of 0.50 V.
• The enhanced performance was attributed to a preferred (220) crystal orientation and the formation of a thin silver oxide layer.

Conclusions:

• Simple anodization is an effective method to enhance Ag catalyst performance for CO2 electroreduction.
• The study provides insights into the surface modifications that improve CO2 conversion efficiency.
• This work offers a potential route for efficient electrochemical CO2 utilization.