Interface Engineering of Silver-Based Heterostructures for CO₂ Reduction Reaction

Area of Science:

• Electrochemistry and Catalysis
• Materials Science
• Computational Chemistry

Background:

• Electrochemical CO2 reduction to CO (CO2RR) is crucial for renewable energy storage and carbon utilization.
• Silver (Ag) catalyzes CO2RR but requires high overpotentials for selectivity.
• Metal-oxide/Ag interfaces offer a promising strategy to improve CO2RR performance.

Purpose of the Study:

• To investigate the catalytic insights of metal-oxide/Ag(111) interfaces for CO2RR using DFT.
• To design and synthesize novel metal-oxide/Ag composites for enhanced CO2 production.
• To understand the synergistic effects between metal oxides and silver for improved catalysis.

Main Methods:

• Density Functional Theory (DFT) calculations to study CO2RR intermediates and reaction pathways on MOx/Ag(111) surfaces.
• Experimental synthesis of various metal-oxide/Ag composites via a two-step approach.
• Electrochemical characterization of synthesized catalysts to evaluate CO2RR activity and selectivity.

Main Results:

• DFT revealed enhanced stabilization of *COOH intermediates and suppressed hydrogen adsorption on MOx/Ag(111) surfaces.
• Synthesized MOx/Ag catalysts demonstrated improved CO activity and selectivity at positive potentials.
• MnO2/Ag catalyst showed a 21.5-fold increase in current density and significantly lower overpotential for CO production compared to pure Ag.

Conclusions:

• Metal-oxide/Ag interfaces effectively enhance CO2RR performance by stabilizing key intermediates and suppressing side reactions.
• The study proposes a rational design strategy for CO2RR catalysts based on synergistic metal-oxide/metal interactions.
• Engineered interfaces, particularly MnO2/Ag, show great potential for efficient and selective electrochemical CO production.