Dual Defect-Engineered BiVO₄ Nanosheets for Efficient Peroxymonosulfate Activation

Area of Science:

• Materials Science
• Environmental Chemistry
• Nanotechnology

Background:

• Defect and heteroatom doping are crucial for optimizing photocatalyst performance.
• Combining these strategies offers a powerful approach for designing advanced photocatalysts.

Purpose of the Study:

• To synthesize dual defect-engineered BiVO4 nanosheets (BVO-N-OV) via N doping and oxygen vacancies.
• To investigate the synergistic effects of these defects on photocatalytic activity.
• To evaluate the performance of BVO-N-OV in degrading ciprofloxacin (CIP) using peroxymonosulfate (PMS) under visible light.

Main Methods:

• Ammonium oxalate-assisted thermal treatment of BiVO4 nanosheets to introduce N doping and oxygen vacancies.
• Characterization of material properties, including band structure and surface active sites.
• Photocatalytic degradation experiments using the BVO-N-OV/PMS system under visible light illumination.

Main Results:

• The BVO-N-OV nanosheets exhibited enhanced visible light absorption, charge transfer efficiency, and increased active sites.
• The BVO-N-OV/PMS system showed significantly improved CIP removal rates, with rate constants 7.9, 1.9, and 6.6 times higher than pristine BiVO4, BVO-OV, and BVO-N, respectively.
• The system demonstrated stable and excellent performance across a wide pH range (3.0-11.0) and in the presence of various anions.

Conclusions:

• The synergistic effect of N doping and oxygen vacancies in BiVO4 significantly enhances its photocatalytic activity for CIP degradation.
• The developed BVO-N-OV/PMS system is a highly efficient and stable solution for visible-light-driven wastewater treatment.
• This study provides valuable insights into defect and doping engineering for designing advanced photocatalyst/PMS systems.