Engineering Cu⁺/Cu⁰ Interfaces With Lanthanum Doping for Efficient CO₂-to-C₂₊ Conversion

Area of Science:

• Catalysis
• Materials Science
• Electrochemistry

Background:

• Copper-based catalysts are promising for CO2 conversion to C2+ products.
• Instability of active Cu+ sites hinders C-C coupling and catalyst performance.
• Developing stable and efficient catalysts for CO2 reduction is critical.

Purpose of the Study:

• To investigate the effect of Lanthanum (La) doping on CuₓO catalysts for CO2 reduction.
• To understand how La doping influences Cu+ stability and C-C coupling kinetics.
• To optimize La-doped CuₓO catalysts for enhanced C2+ selectivity and stability.

Main Methods:

• Synthesis of Lanthanum (La)-doped CuₓO catalysts with varying La/Cu ratios.
• Density functional theory (DFT) calculations to model electronic and structural effects.
• In situ spectroscopic characterization to analyze catalyst behavior during CO2 reduction reaction (CO2RR).

Main Results:

• La doping stabilizes Cu+ species by facilitating charge transfer and increasing grain boundary density.
• Optimized La-doped CuₓO-2 catalyst achieved 45.2% C2H4 Faradaic efficiency and 75.4% C2+ FE.
• The catalyst demonstrated exceptional stability, retaining over 90% activity after 24 hours of operation.
• Enhanced *CO dimerization kinetics and lowered C-C coupling barriers were observed.

Conclusions:

• Rare-earth doping, specifically La, offers a rational strategy for stabilizing active Cu+ sites in copper-based CO2 reduction catalysts.
• La doping effectively modulates electronic properties and grain boundary structures, promoting C-C coupling and improving catalyst durability.
• The developed La-CuₓO catalysts show significant potential for efficient and stable electrochemical CO2 conversion to valuable C2+ products.