6.1 Proyectos de investigación científica

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https://hdl.handle.net/20.500.12390/383

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Examinando 6.1 Proyectos de investigación científica por Autor "rp00096"
  • Publicación
    Synthesis and Characterization of ZnO Nanorod Films on PET for Photocatalytic Disinfection of Water
    (Sycamore Global Publications, 2015-01-01)
    Sanchez, Luis
    ;
    Guz, Lucas
    ;
    García, Pilar
    ;
    Ponce, Silvia
    ;
    Goyanes, Silvia
    ;
    Marchi, María Claudia
    ;
    Candal, Roberto
    ;
    Rodriguez, Juan
    ZnO nanorods (ZnO NRs) were grown on ZnO seeded polyethylene tert-phtalate(PET) substrates obtained from recycled soda bottles at low temperatures (90°C) from Zn2+precursors in alkaline aqueous solution. The ZnO seeds were deposited on the PET substrates by spray gel (SG) or dip coating (DC) from a ZnO methanol sol. In the case of SG, the PET substrate was heated at 90 °Cduring the spray process. By the other hand the ZnO seed layers obtained by dip coating were heated at 90°C or 130°C for 10 minutes among coatings. Before seeding two procedures were made on PET surface forimproving seed adhesion: 1) PET surface was mechanically roughened with sand paper 1200. 2) PET surface was chemically treated with a solution of NaOH in ethanol. The relationship between the microstructure of the ZnO NRs films as function of the PET surface treatment and the photocatalytic antibacterial activity for E. Colidisinfection, was determined through a detailed characterizationof the material. The highest photocatalytic antibacterial activity was performed by ZnONRs films grown on seeds deposited by dip coating with 10 layers, 5 minutes of chemical treatment of PET surface and a thermal treatment at 130° C among coatings. With these films the population of viable E. Colidropped more than seven orders, from 3x108to 101CFU.
  • Publicación
    The role of seeding in the morphology and wettability of ZnO nanorods films on different substrates
    (Elsevier, 2013-08)
    Rodríguez, Juan
    ;
    Onna, Diego
    ;
    Sánchez, Luis
    ;
    Marchi, M. Claudia
    ;
    Candal, Roberto
    ;
    Ponce, Silvia
    ;
    Bilmes, Sara A.
    Spray pyrolysis (SP) and spray-gel (SG) techniques were used to deposit ZnO seeds on Fluor doped tin oxide glasses (FTO), heated at 350 °C or 130 °C, and PET heated at 90 °C. The effect of seeding on the morphology and wettability of ZnO nanorods (NRs) films grown by wet chemical methods was analyzed. The morphology and wettability of ZnO NRs films depend on the seeding process. SP seeds formed from zinc acetate dissolved in water ethanol mixtures yield vertically aligned ZnO NRs, whose diameters and dispersion size are determined by the ethanol/water ratio in the precursor solution. SG seeds formed from a methanol ZnO sol produce a ring patterned distribution on the FTO substrate. The drying of ZnO sol drops impinging on the substrate produces high density of seeds along a ring yielding textured films with NRs vertically oriented on the rings and multi-oriented outside them. This effect was not observed when ZnO NRs grown onto the ZnO/PET substrate, however rod diameter is related with the density of seeds. This way to control the density and diameter of NRs deposited onto a substrate modify the wettability and opens new possibilities for the design of tailored nanomaterials for photochemical applications. Both type of NRs films showed a strong luminescence emission in the UV and in the blue, associated with surface and intrinsic defects.