Defect Engineered Bi₂Te₃ Nanosheets with Enhanced Haloperoxidase Activity for Marine Antibiofouling

Area of Science:

• Materials Science
• Nanotechnology
• Biotechnology

Background:

• Bismuth telluride (Bi2Te3) nanosheets are explored as nanozymes.
• Defect engineering in materials can enhance catalytic activity.
• Haloperoxidase (hPOD) mimics are sought for eco-friendly applications.

Purpose of the Study:

• To engineer defective Bi2Te3 nanosheets (d-Bi2Te3-X) with enhanced haloperoxidase (hPOD) activity.
• To evaluate the bactericidal and antimicrofouling properties of these nanozymes.
• To demonstrate defect engineering as a strategy for developing novel nanozymes.

Main Methods:

• Controlled NaOH etching of Bi2Te3 nanosheets to create defects.
• Characterization using microscopy and spectroscopy.
• Assays for hPOD activity, antibacterial efficacy (Staphylococcus aureus, Pseudomonas aeruginosa), and antimicrofouling performance on coated surfaces.

Main Results:

• NaOH etching (up to 250 µL) created defects (d) in Bi2Te3, significantly enhancing hPOD activity (d-Bi2Te3-250 showed ~8x improvement).
• d-Bi2Te3-250 exhibited potent antibacterial activity, with 1% viability for S. aureus and 45% for P. aeruginosa.
• Significant inhibition of microfouling (up to ~73%) was observed in laboratory and real-world seawater conditions.

Conclusions:

• Defect engineering in non-transition metal chalcogenides like Bi2Te3 can induce potent antibacterial and antimicrofouling properties.
• The defective Bi2Te3 nanozymes effectively produce hypohalous acid, leading to bactericidal effects.
• This approach presents a cost-effective and eco-friendly alternative to noble metal-based materials for antimicrobial applications.