Dynamic Dual-Site Relay Catalysis Enables Selective Solar-Driven CO₂ Reduction Toward Ethanol

Area of Science:

• Materials Science
• Catalysis
• Renewable Energy

Background:

• Photocatalytic CO2 reduction to ethanol (C2H5OH) is a promising sustainable carbon recycling pathway.
• Current methods face limitations due to inefficient carbon-carbon (C-C) coupling under visible light.

Purpose of the Study:

• To develop a novel photocatalyst for efficient and selective CO2 to ethanol conversion.
• To elucidate the mechanism behind enhanced C-C coupling for ethanol synthesis.

Main Methods:

• Fabrication of defect-engineered WO3-x/In single atom sites (SAs) photocatalyst.
• Utilized in situ spectroscopy and Density Functional Theory (DFT) calculations.
• Performed scaled-up experiments under natural sunlight illumination.

Main Results:

• Achieved high ethanol selectivity (97.43% electrons, 86.35% yield).
• Demonstrated a dynamic dual-site relay mechanism involving W-oxygen vacancy (V_O) and In SAs.
• Confirmed efficient CO2 to ethanol conversion under natural sunlight in a scaled reactor.

Conclusions:

• The W-V_O site acts as a CO supply hub, while In SAs facilitate selective CO coupling.
• The engineered photocatalyst significantly improves photogenerated carrier utilization for solar fuel synthesis.
• This work offers a design strategy for efficient photocatalytic CO2 reduction and scalable solar fuel production.