Plasma-Modified Dendritic Cu Catalyst for CO₂ Electroreduction.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient catalysts for selective hydrocarbon production via CO2 electroreduction (CO2RR) is critical for sustainable chemistry.
• Copper-based catalysts are promising for CO2RR, but achieving high selectivity towards specific products remains a challenge.
• Catalyst morphology and surface chemistry significantly influence catalytic activity and selectivity.

Purpose of the Study:

• To investigate the effect of low-pressure oxygen plasma treatment on dendritic copper (Cu) catalysts for CO2RR.
• To elucidate the role of catalyst morphology versus initial oxide species in determining catalytic performance and selectivity.
• To establish structure-selectivity correlations for rational catalyst design in CO2RR.

Main Methods:

• Modification of dendritic Cu catalysts using low-pressure oxygen plasma pretreatment.
• Electrocatalytic CO2 reduction reaction (CO2RR) experiments to assess catalyst performance.
• Operando X-ray absorption fine-structure spectroscopy (XAFS) and quasi in situ X-ray photoelectron spectroscopy (XPS) for in-situ characterization.

Main Results:

• Plasma-treated dendritic Cu catalysts exhibited enhanced selectivity towards C2 and C3 hydrocarbon products.
• Catalyst morphology was identified as a more critical factor than the initial presence of copper oxides (CuₓO).
• CuₓO species were found to be unstable under CO2RR conditions, suggesting their limited role in long-term performance.

Conclusions:

• Plasma pretreatment is an effective strategy for tailoring dendritic Cu catalyst morphology and enhancing CO2RR selectivity.
• The study highlights a strong correlation between catalyst structure and selectivity in CO2RR.
• Findings provide insights for designing improved catalysts by focusing on morphology control via plasma treatments.