Silver-TiO2 nanocomposites: Synthesis and harmful algae bloom UV-photoelimination
Por:
Rodríguez-González V., Alfaro S.O., Torres-Martínez L.M., Cho S.-H., Lee S.-W.
Publicada:
1 ene 2010
Resumen:
Silver TiO2 nanocomposites were synthesized by two methods: silver UV photodeposition (Ag/P25) and a sol-gel process incorporating silver nitrate during the titanium alkoxide gelling step (TiO2-Ag). The obtained nanocomposites were characterized by means of XRD, N2 adsorption, XPS, and DRS. All the silver-TiO2 semiconductors have anatase as the principal crystalline TiO2 phase and the average band gap was found in the edge of the visible-ultraviolet region (3.26eV). According to XPS and HAADF-STEM studies, highly dispersed silver nanoparticles were found on the titania surface as Ag°. The photocatalytic effects of the silver TiO2 nanocomposites on the killing of marine algae were examined by using either Amphidinium carterae (red tide) or noxious Tetraselmis suecica (green tide) as a probe. After 1h under UV irradiation, both harmful algae were inactivated by the silver nanocomposites. The fatal damages to these microorganisms induced by the TiO2-Ag sol-gel semiconductor occurred faster than those promoted by the Ag/P25 and TiO2 sol-gel isolated supports. In addition to the biocide properties of silver in aqueous medium, the silver nanoparticles acted as electron traps, retarding electron-hole recombination, which enhanced the photocatalytic activity. © 2010 Elsevier B.V.
Filiaciones:
IPICYT, División de Materiales Avanzados, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José 2055 Col., Lomas 4a. sección C.P. 78216, San Luis Potosí, S.L.P., Mexico
Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Ciudad Universitaria, C.P. 66451, San Nicolás de los Garza, N.L., Mexico
Universidad Autónoma de Nuevo León, Facultad de Ingeniería Civil, Instituto de Ingeniería Civil, Departamento de Ecomateriales y Energía, Av. Universidad S/N, C.P. 66451, San Nicolás de los Garza, Nuevo León, Mexico
Department of Materials Engineering, Sun Moon University, Galsan-Ri, Tangjung-Myon, Asan Chungnam, 336-708, South Korea
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