Heterogeneous Single-Atom Catalyst for Visible-Light-Driven High-Turnover CO₂ Reduction: The Role of Electron...

Area of Science:

• Materials Science
• Catalysis
• Renewable Energy

Background:

• Visible-light-driven conversion of carbon dioxide (CO2) into chemical fuels offers a promising route for sustainable energy.
• Integrating homogeneous and heterogeneous photocatalysts can optimize light harvesting and catalysis, but efficient charge transfer remains a challenge.

Purpose of the Study:

• To design a highly active and durable heterogeneous photocatalyst for CO2 conversion.
• To improve photoexcited electron transfer between light absorbers and catalytic sites.

Main Methods:

• Synthesized single-atom cobalt (Co) sites coordinated on partially oxidized graphene nanosheets.
• Utilized the graphene support to bridge homogeneous light absorbers with single-atom catalytic sites.
• Evaluated the photocatalytic performance for CO2 conversion to CO.

Main Results:

• Achieved a high turnover number (TON) of 678 for CO production.
• Obtained an unprecedented turnover frequency (TOF) of 3.77 min⁻¹, surpassing state-of-the-art heterogeneous photocatalysts.
• Demonstrated efficient transfer of photoexcited electrons facilitated by the graphene support.

Conclusions:

• Single-atom cobalt sites on graphene nanosheets function as an effective heterogeneous catalyst for photocatalytic CO2 conversion.
• The design highlights the importance of charge kinetics and bridging homogeneous and heterogeneous systems for enhanced photocatalysis.
• This approach offers insights into designing advanced catalytic sites for CO2 utilization and renewable fuel production.