Surface characterization of nanostructured TiO2 and carbon blacks composites by dye adsorption and photoelectrochemical studies
Por:
Rincón M.E., Trujillo-Camacho M.E., Cuentas-Gallegos A.K., Casillas N.
Publicada:
1 ene 2006
Resumen:
Photocatalysts based on nanostructured TiO2 and carbon blacks (CB) particles were obtained by chemical (sol-gel) and physical (mechanical grinding) preparation techniques. Characterization of these samples by XRD, FT-IR and dye adsorption studies was combined with optical and scanning photoelectrochemical analysis in an attempt to explain the photodegradation efficiency of these materials. The superior adsorption of sol-gel materials in the aqueous dye solutions did not account for the differences observed in photocatalytic activity, where the sol-gel composite outperforms the physical mixture or TiO2 alone by one digit. Data on the photoelectrochemical activity of these composites showed the abundance of inactive sites in the mixtures, while the sol-gel composite showed a uniform active surface. Rectification properties brought up by carbon in sol-gel composites and plus the abundance of hydroxyl groups on the oxide surface are proposed to be responsible for the long-term activity of these photocatalysts. © 2006 Elsevier B.V. All rights reserved.
Filiaciones:
Rincón M.E.:
Centro de Investigación en Energía-UNAM, Apartado Postal 34, Temixco, 62580 MOR, Mexico
Trujillo-Camacho M.E.:
Centro de Investigación en Energía-UNAM, Apartado Postal 34, Temixco, 62580 MOR, Mexico
Cuentas-Gallegos A.K.:
Centro de Investigación en Energía-UNAM, Apartado Postal 34, Temixco, 62580 MOR, Mexico
Casillas N.:
Universidad de Guadalajara, Departamento de Química, Blvd. Marcelino Garcia Barragan 1451, Guadalajara, Mexico CP 44430, Mexico
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