Manipulating Au-CeO₂ Interfacial Structure Toward Ultrahigh Mass Activity and Selectivity for CO₂ Reduction

Area of Science:

• Materials Science
• Catalysis
• Electrochemistry

Background:

• Improving catalysts for carbon dioxide reduction reactions (CO2 RR) requires enhancing both mass activity and selectivity.
• Current Au-based catalysts often exhibit limited mass activity (typically <10 mA mg−1 Au at -0.6 V).

Purpose of the Study:

• To develop a novel strategy for enhancing CO2 RR performance by manipulating the interface between Au and CeO2 nanoparticles.
• To investigate the effect of surface charge tuning on the interfacial structure and catalytic activity.

Main Methods:

• Synthesized small-size Au (3.5 nm) and CeO2 nanoparticles.
• Adjusted the surface charge of Au and CeO2 to engineer the interfacial structure.
• Characterized the catalyst's performance in CO2 RR, including mass activity and Faradaic efficiency.
• Evaluated the catalyst's long-term stability.

Main Results:

• The optimized AuCeO2/C catalyst achieved a high mass activity of 139 mA mg−1 Au for CO production at -0.6 V.
• A CO Faradaic efficiency (FE_CO) of 97% was obtained, indicating high selectivity.
• The engineered interface enhanced CO2 adsorption and catalyst utilization.
• The catalyst demonstrated excellent long-term stability due to strong Au-CeO2 interaction.

Conclusions:

• A charge-guided approach effectively constructs interfacial structures for improved CO2 RR.
• Tuning the interface of Au and CeO2 nanoparticles is a promising strategy for developing highly active and selective catalysts.
• This work provides insights for designing advanced catalysts for CO2 conversion and other electrochemical applications.