Outstanding CO₂ Photoreduction in Single-Atom Thulium Modified Carbon Nitride

Area of Science:

• Materials Science
• Catalysis
• Renewable Energy

Background:

• Photocatalytic reduction of carbon dioxide (CO2) is crucial for renewable energy generation.
• Enhancing active sites and charge carrier separation are key challenges in CO2 photoreduction.
• Graphitic carbon nitride (g-C3N4) based materials show promise but require further optimization.

Purpose of the Study:

• To develop a highly efficient CO2 reduction photocatalyst using a thulium (Tm) single atom tailoring strategy.
• To introduce carbon vacancies in porous tubular g-C3N4 to enhance catalytic performance.
• To investigate the mechanistic insights into the role of Tm single atoms and carbon vacancies.

Main Methods:

• Synthesis of porous tubular g-C3N4 modified with Tm single atoms and carbon vacancies.
• Characterization of the material's structure, properties, and photocatalytic activity.
• Analysis of reaction pathways and intermediate formation during CO2 photoreduction.

Main Results:

• The Tm-tailored g-C3N4 exhibited superior CO2 reduction performance with a CO yield of 199.47 µmol g⁻¹ h⁻¹ and 96.8% CO selectivity.
• Apparent quantum efficiency reached 0.84%, demonstrating effective light utilization.
• In-plane Tm sites and Tm-N charge transfer channels significantly enhanced electron transfer and CO2 activation, promoting *COOH intermediate formation.

Conclusions:

• The Tm single atom strategy effectively enriches active sites and promotes charge separation in g-C3N4 for enhanced CO2 photoreduction.
• The developed photocatalyst offers excellent performance and stability, surpassing existing g-C3N4 based materials.
• This work provides valuable guidelines for designing single-atom photocatalysts for solar fuel production and offers mechanistic understanding.