Enhancement of bacterial inactivation of BiOBr nanoflower through oxygen vacancy engineering

Abstract In recent years, various strategies focused on regulating the different defect types and concentrations have been put forward to alter the photo- or electro-catalytic performance of nanomaterials (NMs), such as chemical vapor deposition, thermal annealing, heavy ion irradiation, etc. Herein, a simple strategy for regulating the concentration of oxygen vacancies was developed by in-situ Bi reduction of BiOBr nanoflowers (Bi-BiOBr), largely influencing its photocatalytic activities under the visible light irradiation. The first-principle computation and experimental results revealed that the enhanced doped Bi caused high concentration of oxygen vacancy, thus effectively improving the transfer and separation of photogenerated e-/h+ pairs. High concentration of reactive species such as superoxide radical and singlet oxygen was obtained, which led to an efficient antibacterial activity. Meanwhile, Bi-BiOBr exhibited strong binding ability to bacterial cells due to its abundant oxygen vacancy, showing excellent photodynamic performance under visible light irradiation.