Inactivation of E. Coli in Water Using Photocatalytic, Nanostructured Films Synthesized by Aerosol Routes

Catalysts

Jinho Park¹  Eric Kettleson¹  Woo-Jin An¹  Yinjie J. Tang¹ 

[1] Aerosol and Air Quality Research Laboratory, Department of Energy, Environmental and Chemical Engineering, School of Engineering and Applied Science, Washington University in St. Louis, Campus Box 1180, St. Louis, MO 63130, USA; E-Mails:

关键词: aerosol chemical vapor deposition;    photocatalysis;    photoelectrochemical inactivation;    TiO₂;    UVA;   

DOI  :  10.3390/catal3010247

来源: mdpi

【 摘 要 】

TiO₂ nanostructured films were synthesized by an aerosol chemical vapor deposition (ACVD) method with different controlled morphologies: columnar, granular, and branched structures for the photocatalytic inactivation of Escherichia coli (E. coli) in water. Effects of film morphology and external applied voltage on inactivation rate were investigated. As-prepared films were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffractometry (XRD), and UV-VIS. Photocatalytic and photoelectrochemical inactivation of E. coli using as-prepared TiO₂ films were performed under irradiation of UVA light (note: UVA has a low efficiency to inactivate E. coli). Inactivation rate constants for each case were obtained from their respective inactivation curve through a 2 h incubation period. Photocatalytic inactivation rate constants of E. coli are 0.02/min (using columnar films), and 0.08/min (using branched films). The inactivation rate constant for the columnar film was enhanced by 330% by applied voltage on the film while that for the branched film was increased only by 30%. Photocatalytic microbial inactivation rate of the columnar and the branched films were also compared taking into account their different surface areas. Since the majority of the UV radiation that reaches the Earth’s surface is UVA, this study provides an opportunity to use sunlight to efficiently decontaminate drinking water.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.