title: Enhanced visible-light-driven photocatalytic bacteria disinfection by g-C3N4-AgBr.
abstract: g-C3N4-AgBr was synthesized by depositing AgBr nanoparticles onto g-C3N4. Scanning electron microscopy (SEM), Transmission electron microscope (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectra (DRS) and Photoluminescence (PL) spectra were employed to characterize the as-synthesized photocatalysts. The disinfection activities towards representative Gram-negative strain E. coli and Gram-positive strain S. aureus were examined under visible light irradiation. Complete inactivation of 3×106CFU/mL viable cell density was reached in 60min for E. coli and 150min for S. aureus, respectively. Ag+released from the photocatalysts did not contribute to the photocatalytic disinfection process. Direct contact of g-C3N4-AgBr composites and bacterial cells, as well as the presence of O2was indispensable for the cell inactivation. Photo-generated holes, surface bounded OH, and indirect generation of intracellular active species played important roles in disinfection process of g-C3N4-AgBr under visible light irradiation. The disruption of outside structure of cells as well as inner cell injury led to the inactivation. High pH condition led to increasing the cell disinfection due to the generation of surface bounded OH.
authors.affiliation: The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Deng
authors.affiliation: The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, PR China.
authors.forename: Jialiang
authors.initials: J
authors.lastname: Liang
authors.affiliation: The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, PR China.
authors.forename: Mian
authors.initials: M
authors.lastname: Li
authors.affiliation: The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, PR China. Electronic address: tongmeiping@pku.edu.cn.
authors.forename: Meiping
authors.initials: M
authors.lastname: Tong
mesh_terms: D001419:Bacteria / Q000187:drug effects*; D001965:Bromides / Q000737:chemistry*; D002384:Catalysis; D004203:Disinfection / Q000379:methods*; D004926:Escherichia coli / Q000187:drug effects; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry*; D010777:Photochemistry / Q000379:methods*; D018030:Silver Compounds / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D001965:Bromides; D018030:Silver Compounds; C047751:silver bromide
keywords: Active species; Bacteria disinfection; Photocatalysis; Visible light irradiation; g-C(3)N(4)-AgBr