Selective CO₂ -to-C₂ H₄ Photoconversion Enabled by Oxygen-Mediated Triatomic Sites in Partially Oxidized Bimetallic...

Area of Science:

• Materials Science
• Catalysis
• Renewable Energy

Background:

• Selective photoreduction of carbon dioxide (CO2) to C2 fuels is crucial for sustainable energy but hindered by inefficient C-C coupling.
• Existing photocatalysts often struggle with low product yield and selectivity due to kinetic limitations.

Purpose of the Study:

• To develop a novel strategy for enhancing C-C coupling in CO2 photoreduction.
• To improve the selectivity and yield of C2 fuel production using photocatalysis.

Main Methods:

• Synthesis of FeCoS2 atomic layers with varying oxidation degrees.
• Characterization using X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge spectroscopy (XANES).
• Experimental evaluation and theoretical calculations to understand reaction mechanisms.

Main Results:

• Successfully introduced Co-O-Fe triatomic sites by incorporating oxygen into FeCoS2 atomic layers.
• Demonstrated enhanced charge aggregation around oxygen sites, promoting C-C coupling of *COOH intermediates.
• Achieved a C2H4 formation rate of 20.1 μmol g⁻¹ h⁻¹ with 82.9% product selectivity and 96.7% electron selectivity.

Conclusions:

• Triatomic sites effectively promote C-C coupling for selective C2 fuel formation in CO2 photoreduction.
• Mildly oxidized FeCoS2 atomic layers represent a highly efficient photocatalyst for C2 fuel production.
• The findings offer a promising pathway for developing advanced catalysts for CO2 conversion.