Reconstructed Copper Compound by Cerium Leaching for Enhanced Electrochemical CO₂-to-Ethylene Conversion

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Electrochemical CO2 reduction (e-CO2RR) is crucial for sustainable chemical production.
• Developing selective electrocatalysts for multi-carbon products remains a significant challenge.
• Tuning catalyst structure is key to enhancing e-CO2RR performance.

Purpose of the Study:

• To investigate the performance of Ce-incorporated Cu oxide (CeCuO_x) for selective electrochemical CO2 reduction.
• To understand the structural reconstruction and mechanism of CeCuO_x during e-CO2RR.
• To achieve high selectivity towards C2H4 production.

Main Methods:

• Synthesis of CeCuO_x electrocatalyst.
• Electrochemical characterization including cyclic voltammetry and chronoamperometry.
• In situ analysis to study catalyst reconstruction and electronic structure.
• Gas chromatography to quantify product selectivity and Faraday efficiency.

Main Results:

• CeCuO_x exhibited prominent performance for selective C2H4 production with a high Faraday efficiency (FE) of 55.39% at -0.93 V.
• The catalyst achieved a partial current density of -39.50 mA cm^-2 at -1.03 V, outperforming Cu oxide and Cu.
• Structural analysis revealed that CeCuO_x reconstructs to oxygen-contained Cu with optimized electronic structure and Cu⁰/(Cu⁺+Cu²⁺) ratio.
• Enhanced generation and activation of C1-2 intermediates were observed, leading to high C2H4 selectivity.

Conclusions:

• CeCuO_x demonstrates excellent selectivity and efficiency for electrochemical CO2 reduction to C2H4.
• Catalyst reconstruction, driven by Ce leaching and in situ reduction, optimizes the electronic structure and facilitates water cleavage.
• This work provides insights into structure-performance relationships for boosting CO2 conversion to multi-carbon products.