INVESTIGADORES
ALFANO Orlando Mario
artículos
Título:
Photocatalytic Inactivation of Bacterial Spores using TiO2 Films with Silver Deposits
Autor/es:
ZACARIAS, S.M.; SATUF, M.L.; VACCARI, M.C.; ALFANO, O.M.
Revista:
CHEMICAL ENGINEERING JOURNAL
Editorial:
ELSEVIER SCIENCE SA
Referencias:
Lugar: Amsterdam; Año: 2015 vol. 266 p. 133 - 140
ISSN:
1385-8947
Resumen:
The present
work evaluates the enhancement of the photocatalytic inactivation of bacterial
spores employing TiO2 films with silver deposits compared to TiO2 films without
metal deposition. Bacillus subtilis spores spread over TiO2 films with
different silver contents were irradiated with artificial UV-A light. The
performances of the coatings were evaluated by the quantum efficiency
parameter, which relates the inactivation rate with the radiation absorption
rate by the coating. Spectral diffuse transmittance and reflectance
measurements of the films were carried out to evaluate the fraction of energy
absorbed by the coatings. TiO2 and Ag/TiO2 films characterization also included
X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), X-ray photoelectron
spectroscopy (XPS), and Scanning Electron Microscopy (SEM). A notable increase
in the photocatalytic inactivation was observed by increasing the silver
content of the coatings, reaching a maximum quantum efficiency with the sample
containing 1.09 wt.% Ag/TiO2. The addition of higher amounts of silver rendered
lower inactivation, thus indicating the existence of an optimum Ag/TiO2
relation.