Visible light activated bactericidal effect of TiO2/Fe3O4 magnetic particles on fish pathogens

✍ Scribed by T.C. Cheng; K.S. Yao; N. Yeh; C.I. Chang; H.C. Hsu; Y.T. Chien; C.Y. Chang

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 393 KB
• Volume: 204
• Category: Article
• ISSN: 0257-8972
• DOI: 10.1016/j.surfcoat.2009.06.050

✦ Synopsis

TiO 2 Sol-gel method Fe 3 O 4 Fish pathogens

The purpose of this research is to develop a bactericidal photocatalytic TiO 2 that can be activated by visible light and can be conveniently recollected for reusing. This research synthesizes the 22 to 33 nm TiO 2 /Fe 3 O 4 particles with magnetization of 2.9 emu/g using modified sol-gel method followed by 500 °C calcinations. The experiment verifies that both household fluorescent light (HFL, contains minor UV-A) and visible fluorescent light (VFL, contains no UV-A) can activate the photocatalytic activity of TiO 2 /Fe 3 O 4 particles as did ultraviolet A light (UV-A, 360 nm). Regular magnets can be used to separate TiO 2 /Fe 3 O 4 particles from solution. There have not been any significant weight and photocatalytic activity lost during 2 reusings. After 60 min and 120 min VFL irradiation, the bactericidal efficiencies of TiO 2 /Fe 3 O 4 are 35% and 72 % for Streptococcus iniae and 35% and 53% for Edwardsiella tarda, respectively. The results indicate that VFL irradiated TiO 2 /Fe 3 O 4 particles can disinfect fish pathogens in the absence of UV-A and the issue of TiO 2 /Fe 3 O 4 recollection from water for reusing is also resolved.