Anti-bacterial activity of indoor-light activated photocatalysts

• Published in: Applied catalysis. B, Environmental Environmental, 2013-02, Vol.130-131, p.106-111
• Main Authors: Synnott, Damian W., Seery, Michael K., Hinder, Steven J., Michlits, Georg, Pillai, Suresh C.
• Format: Article
• Language: English
• Subjects: Anti-microbial; Anti-MRSA coatings; Antiinfectives and antibacterials; Bacteria; Band gap; Cell wall; Decontamination; Degradation; Degussa P-25; Disinfection; Doping; Emerging pollutants; Escherichia coli; Gram positive and gram negative bacteria; Green and energy efficient synthesis; Hospital acquired infections; Methicillin-resistant Staphylococcus aureus (MRSA); Micro-biology; Microwaves; MRSA; Nanomaterials; P. aerginosa; Photo-activity; Photocatalysis; Photocatalysts; Solar; Staphylococcus aureus; TiO2; Visible light; XPS; Zinc sulfides; ZnO
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2012.10.020

Degradation rate of the bacteria in the presence of the photocatalyst. [Display omitted] ► Nanocrystalline photocatalysts, prepared under ambient conditions using a microwave assisted synthesis. ► These nanomaterials show indoor light photocatalytic activity for the degradation of S. aureus and E. coli. ► A novel energy efficient method (green synthesis) to produce anti-bacterial zinc sulphide. ► The mechanism for the indoor light antibacterial photocatalysis is proposed. Nanocrystalline photocatalysts, prepared under ambient conditions using a microwave assisted synthesis, show indoor light photocatalytic activity for the degradation of Staphylococcus aureus and Escherichia coli. The zinc sulphide (ZnS) nanomaterials, prepared by a microwave assisted synthesis, are shown to be cubic blende structure with an average crystallite size of 4–6nm. The anti-bacterial activity of these nanomaterials is investigated under irradiation from a 60W light bulb and photocatalytic activity is revealed to be due to the defects present in the crystal structure. The ZnS shows anti-bacterial action as both a bacteriostatic and bacteriocidal (88% reduction in the amount of bacteria in 5h) material and the methods of bacterial degradation on the ZnS is discussed. The anti-bacterial actions of these materials were also compared with commercial ZnS and Evonik-Degussa P-25. A detailed mechanism for the light absorption in the visible light region of the microwave prepared ZnS is proposed based on the luminescence spectroscopy.