Defect engineering in a Zn_0.2Cd_0.8S/g-C₃N₄ S-scheme heterojunction for highly selective CO₂-to-CO photoconversion

Area of Science:

• Materials Science
• Catalysis
• Photochemistry

Background:

• CO2 conversion is crucial for sustainability.
• Developing efficient catalysts for CO2 reduction is a major challenge.
• S-scheme heterojunctions show promise for photocatalysis.

Purpose of the Study:

• To construct an S-scheme heterojunction catalyst.
• To investigate the CO2-to-CO conversion performance.
• To understand the role of N-vacancies and charge separation.

Main Methods:

• Synthesized Zn0.2Cd0.8S and N-deficient g-C3N4.
• Fabricated the S-scheme heterojunction.
• Evaluated photocatalytic CO2 reduction under visible light irradiation.
• Analyzed product selectivity and conversion rates.

Main Results:

• The Zn0.2Cd0.8S/N-deficient g-C3N4 heterojunction exhibited 100% selectivity for CO2-to-CO conversion.
• Achieved a high conversion rate of 57.82 µmol g-1 h-1.
• Demonstrated the synergistic effect of N-vacancies and enhanced charge separation.

Conclusions:

• The constructed S-scheme heterojunction is a highly efficient catalyst for CO2-to-CO conversion.
• N-vacancies play a key role in enhancing catalytic activity.
• This work provides insights into designing advanced photocatalysts for CO2 utilization.