Preparation and photocatalytic antibacterial mechanism of porous metastable β-Bi2O3 nanosheets

Effective and safe application of antibacterials has always been an important aspect for their usage. High-efficiency photocatalytic technology driven by visible light for antibacterial action constitutes a practical solution for antibacterial agents and will not harm the human body or the environment. While most studies on β-Bi 2 O 3 materials with good photocatalytic properties under visible light are conducted in the field of optoelectronics , their potential and mechanism as photocatalytic antibacterial agents have not yet been fully explored. Herein, we report the performance of sheet-like metastable β-Bi 2 O 3 material with rich oxygen vacancies and high electron-hole separation efficiency in antibacterial processes, as well as a preliminary exploration of its antibacterial mechanism. The results revealed that the antibacterial activity of the product against E. coli greatly improved in comparison with commercially available α-Bi 2 O 3 owing to its excellent structure and optical properties . In addition, gradient experiments and scavenger experiments have confirmed that the main antibacterial effect of β-Bi 2 O 3 originates from reactive oxygen species (ROS), and the superoxide radical, ·O 2 − , of generated ROS is the key reactive species in the antibacterial process. Through the detection of lipid peroxidation and bacterial respiratory-chain dehydrogenase activity, several pathways were identified for the excellent antibacterial activity of the product.