Highly Active and Selective Electrocatalytic CO₂ Conversion Enabled by Core/Shell Ag/(Amorphous-Sn(IV))...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrochemical CO2 reduction (ECR) offers a pathway for CO2 utilization but faces challenges with overpotential and selectivity.
• Developing efficient catalysts is crucial for practical ECR applications.

Purpose of the Study:

• To design and investigate core/shell Ag/(Amorphous-Sn(IV)) (Ag/(A-Sn(IV))) nanoparticles as catalysts for ECR.
• To explore the effect of amorphous shell thickness on ECR activity and product selectivity.

Main Methods:

• Synthesis of Ag/(A-Sn(IV)) core/shell nanoparticles with varying amorphous shell thicknesses.
• Electrochemical characterization to evaluate catalytic performance, including Faradaic efficiency and partial current density.
• Theoretical calculations to understand the mechanism and structure-activity relationships.

Main Results:

• Ag/(A-Sn(IV)) NPs demonstrated volcano-like activity and selectivity dependent on shell thickness.
• Ultrathin amorphous shells suppressed hydrogen evolution reaction (HER) and enhanced ECR.
• Optimized Ag75/(A-Sn(IV))25 NPs achieved high CO production (88.0% FE) at -0.7 V and high HCOOH production (75.1% FE) at -0.9 V.
• The catalyst exhibited excellent stability over a 12-hour reaction period.

Conclusions:

• Precise control over amorphous shell thickness is key to optimizing Ag/(A-Sn(IV)) catalysts for ECR.
• The optimized catalyst shows high activity, selectivity, and stability for converting CO2 to valuable products.
• Theoretical insights confirm the role of shell thickness in enhancing ECR and inhibiting HER.