Understanding the multifunctionality in Cu-doped BiVO₄ semiconductor photocatalyst

Area of Science:

• Materials Science
• Environmental Chemistry
• Photocatalysis

Background:

• Visible light photocatalysis is crucial for environmental remediation.
• Bismuth Vanadate (BiVO4) is a promising photocatalyst but often requires UV light or suffers from limitations.
• Doping strategies can enhance photocatalytic performance and visible light activity.

Purpose of the Study:

• To synthesize and characterize a visible light-driven Cu-doped BiVO4 photocatalyst.
• To evaluate its efficiency in degrading organic pollutants (Methylene Blue, ibuprofen) and inactivating bacteria (Escherichia coli).
• To understand the mechanism behind the enhanced photocatalytic activity.

Main Methods:

• Microwave hydrothermal synthesis for Cu-doped BiVO4.
• Photocatalytic degradation experiments using Methylene Blue and ibuprofen.
• Bacterial inactivation tests with Escherichia coli.
• Density Functional Theory (DFT) calculations for mechanistic insights.

Main Results:

• Cu-doped BiVO4 exhibited superior photocatalytic activity compared to undoped BiVO4.
• 1wt.% Cu-doped BiVO4 achieved 95% Methylene Blue degradation, 75% ibuprofen degradation, and 85% E. coli inactivation.
• Enhanced visible light absorption and improved charge carrier separation were observed in doped samples.
• DFT calculations revealed in-gap energy states facilitating charge separation and electron trapping.
• The photocatalyst demonstrated excellent stability over three degradation cycles.

Conclusions:

• Cu-doped BiVO4 is a highly efficient and stable visible light photocatalyst.
• The doping-induced in-gap states and oxygen vacancies are key to enhanced performance.
• This material shows significant potential for multifunctional applications in treating complex wastewater.