Positively charged silver improve carbon dioxide electroreduction reaction performance by introducing phosphate.

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Noble metal catalysts like silver (Ag) face efficiency limitations in CO2 electroreduction due to weak intermediate adsorption.
• Positively charged metal surfaces can lower reaction energy barriers, facilitating CO2 conversion.

Purpose of the Study:

• To develop an efficient catalyst for CO2 electroreduction to CO.
• To investigate the role of positively charged metal surfaces in enhancing catalytic activity.

Main Methods:

• In situ synthesis of an Ag3PO4 oxide layer on Ag foil.
• Electrochemical characterization and CO2 electroreduction experiments.
• Density Functional Theory (DFT) calculations.

Main Results:

• The Ag3PO4/Ag catalyst demonstrated a high catalytic selectivity of 94.4% for CO2 to CO conversion.
• The catalyst exhibited increased electrochemical surface area and enhanced adsorption of reaction intermediates.
• DFT calculations confirmed that PO4(3-) stabilizes the positive state of Ag, lowering reaction energy barriers.

Conclusions:

• The Ag3PO4/Ag catalyst significantly improves CO2 electroreduction efficiency and selectivity.
• Internal electron regulation by PO4(3-) enhances catalytic stability and performance.
• This work presents a promising strategy for designing advanced electrocatalysts for CO2 conversion.