Exploring the influence of cell configurations on Cu catalyst reconstruction during CO₂ electroreduction

Area of Science:

• Electrochemistry
• Catalysis
• Materials Science

Background:

• Copper (Cu) catalysts are crucial for electrochemical CO2 reduction reaction (CO2RR) to produce valuable C2+ chemicals.
• The configuration of electrochemical cells, such as membrane electrode assembly (MEA) and H-type cells, can significantly influence catalyst performance.
• Understanding catalyst reconstruction during CO2RR is vital for optimizing C2+ chemical synthesis.

Purpose of the Study:

• To investigate the impact of MEA cell configuration on the reconstruction of Cu catalysts during CO2RR.
• To compare the CO2RR performance and catalyst behavior in MEA cells versus traditional H-type cells.
• To elucidate the relationship between Cu catalyst reconstruction and the selectivity/deactivation in C2+ chemical production.

Main Methods:

• Electrochemical CO2 reduction reaction (CO2RR) studies in both MEA and H-type cells.
• Utilized three distinct Cu-based catalysts with tailored nanostructures.
• Operando and ex-situ X-ray absorption spectroscopy (XAS) for in-depth catalyst characterization.
• Time-resolved CO2RR experiments to monitor reaction evolution.

Main Results:

• MEA cells induce a unique Cu catalyst reconstruction pathway distinct from H-type cells.
• Contrasting selectivity trends for C2+ chemicals were observed between MEA and H-type cells.
• Operando XAS revealed that MEA cells promote Cu2O reduction, leading to altered Cu surfaces.
• Significant Cu reconstruction in MEA cells was identified as a key factor in CO2RR deactivation for C2+ products.

Conclusions:

• MEA cell configuration significantly impacts Cu catalyst reconstruction during CO2RR.
• The unique reconstruction in MEA cells alters catalytic performance and leads to deactivation for C2+ chemical production.
• Tailoring MEA configurations could offer new strategies for controlling Cu catalyst behavior in CO2RR.