title: Photocatalysis-assisted water filtration: using TiO2-coated vertically aligned multi-walled carbon nanotube array for removal of Escherichia coli O157:H7.
abstract: A porous ceramic was coated with vertically aligned multi-walled carbon nanotubes (MWCNTs) by spray pyrolysis. Titanium dioxide (TiO2) nanoparticles were then coated onto this densely aligned MWCNT. The presence of TiO2/MWCNT interfacial arrays was confirmed by X-ray diffraction (XRD), scanning electron microscope-energy dispersive analysis of X-ray (SEM-EDAX) and transmission electron microscope (TEM). This is a novel report in which water loaded with a most dreadful enterohemorrhagic pathogenic strain of Escherichia coli O157:H7 was filtered through TiO2/MWCNT coated porous ceramic filter and then analysed. Bacterial removal performance was found to be significantly lower in control i.e. plain porous ceramic (P<0.05) as compared to TiO2/MWCNT coated ceramic. The photocatalytic killing rate constant for TiO2-ceramic and MWCNT/TiO2-ceramic under fluorescent light was found be 1.45×10(-2) min(-1) and 2.23×10(-2) min(-1) respectively. Further, when I-V characteristics were performed for TiO2/MWCNT composite, it was corroborated that the current under light irradiation is comparatively higher than that in dark, thus proving it to be photocatalytically efficient system. The enhanced photocatalysis may be a contribution of increased surface area and charge transfer rate as a consequence of aligned MWCNT network.
authors.affiliation: N.S. N. Research Centre for Nanotechnology and Bionanotechnology, Jambhul Phata, Kalyan-Badlapur Road, Ambernath (W) 421505, Maharashtra, India.
authors.forename: Goldie
authors.initials: G
authors.lastname: Oza
authors.forename: Sunil
authors.initials: S
authors.lastname: Pandey
authors.forename: Arvind
authors.initials: A
authors.lastname: Gupta
authors.forename: Sachin
authors.initials: S
authors.lastname: Shinde
authors.forename: Ashmi
authors.initials: A
authors.lastname: Mewada
authors.forename: Pravin
authors.initials: P
authors.lastname: Jagadale
authors.forename: Maheshwar
authors.initials: M
authors.lastname: Sharon
authors.forename: Madhuri
authors.initials: M
authors.lastname: Sharon
mesh_terms: D000327:Adsorption; D002384:Catalysis / Q000528:radiation effects; D002516:Ceramics; D003460:Crystallization; D019453:Escherichia coli O157 / Q000302:isolation & purification*; D005374:Filtration / Q000295:instrumentation / Q000379:methods*; D007700:Kinetics; D008027:Light; D050296:Microbial Viability / Q000528:radiation effects; D053761:Nanocomposites / Q000737:chemistry / Q000648:ultrastructure; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D013052:Spectrometry, X-Ray Emission; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D014025:Titanium / Q000494:pharmacology*; D014867:Water; D014961:X-Ray Diffraction
chemical_list: D037742:Nanotubes, Carbon; D014867:Water; C009495:titanium dioxide; D014025:Titanium
keywords: Escherichia coli O157:H7; MWCNTs; Photocatalysis; Porous ceramic candle; TiO(2); Water filter