bactericidal performance of visible-light responsive titania photocatalyst with silver nanostructures杀菌性能的可见光响应二氧化钛光催化剂与银纳米结构.pdf

Bactericidal Performance of Visible-Light Responsive Titania Photocatalyst with Silver Nanostructures Ming-Show Wong1,2., Der-Shan Sun3., Hsin-Hou Chang2,3,4* 1 Department of Materials Science and Engineering, National Dong-Hwa University, Hualien, Taiwan, 2 Nanotechnology Research Center, National Dong-Hwa University, Hualien, Taiwan, 3 Department of Molecular Biology and Human Genetics, Tzu-Chi University, Hualien, Taiwan, Republic of China, 4 Tzu-Chi University Center for Vascular Medicine, Tzu-Chi University, Hualien, Taiwan, Republic of China Abstract Background: Titania dioxide (TiO ) photocatalyst is primarily induced by ultraviolet light irradiation. Visible-light responsive 2 anion-doped TiO2 photocatalysts contain higher quantum efficiency under sunlight and can be used safely in indoor settings without exposing to biohazardous ultraviolet light. The antibacterial efficiency, however, remains to be further improved. Methodology/Principal Findings: Using thermal reduction method, here we synthesized silver-nanostructures coated TiO2 thin films that contain a high visible-light responsive antibacterial property. Among our tested titania substrates including TiO2, carbon-doped TiO2 [TiO2 (C)] and nitrogen-doped TiO2 [TiO2 (N)], TiO2 (N) showed the best performance after silver coating. The synergistic antibacterial effect results approximately 5 log reductions of surviving bacteria of Escherichia coli, Streptococcus pyogenes, Staphylococcus aureus and Acinetobacter baumannii. Scanning electron microscope analysis indicated that crystalline silver formed unique wire-like nanostructures on TiO2 (N) substrates, while formed relatively straight and thicker rod-shaped precipitates on the other two titania