Abstract
Nosocomial infections and food spoilage, caused by different airborne bacteria, is of major concern and titania nanostructure coated surfaces are effective in reducing pathogenic bacteria present in the indoor air. In the present study comparative photocatalytic disinfection ability of pure titania nanotube (TNT) and 1% iron-doped TNT coated wood surface, to disinfect airborne bacteria, has been examined. Prepared nanotubes (both pure and iron doped) were characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Brunauer-Edward-Teller surface area measurement, and band gap energy calculations. Nanotubes were coated on wood surfaces using a novel and green method of coating using a natural resin as the binding agent. Coated wood surfaces were found effective in reducing important airborne bacterial species Pseudomonas aeruginosa (Gram negative) and Staphylococcus aureus (Gram positive) present in indoor air. With a 70% reduction in the population of P. aeruginosa being observed when pure TNT coated wood surfaces were exposed to fluorescent light for 2 h. In the case of 1% iron-doped TNT coated wood surfaces, P. aeruginosa species were completely degraded within 75 min of exposure to fluorescent light. Similar trends were observed with S. aureus, with 80% removal in the case of pure TNT coated wood surface after 2 h, and 100% removal within 90 min, when 1% iron-doped TNT coatings were placed under fluorescent light.