Navegando por Autor "Tavares, Marileide L.A."
Agora exibindo 1 - 2 de 2
- Resultados por página
- Opções de Ordenação
Artigo Fast photocatalytic degradation of an organic dye and photoluminescent properties of Zn doped In(OH)3 obtained by the microwave-assisted hydrothermal method(Elsevier, 2014-11) Tavares, Marileide L.A.; Lovisa, Laura Ximena; Araújo, Vinícius Dantas; Silva, Elson Longo da; Li, Maximo Siu; Nascimento, Rubens Maribondo do; Paskocimas, Carlos Alberto; Delmonte, Maurício Roberto Bomio; Motta, Fabiana Villela daCrystalline zinc-doped indium hydroxide structures were prepared by the rapid and efficient microwave-assisted hydrothermal (MAH) method. X-ray diffraction (XRD), field emission gun-scanning electron microscopy (FEG-SEM), photoluminescence (PL) and UV–visible (UV–vis) spectroscopy were used to characterization the materials. FEG-SEM images revealed that pure In(OH)3 samples and Zn-doped samples exhibit nanocubic morphologies with a wide range of particle sizes. Relative intensities of PL emissions decreased as the Zn ion concentration increased from 0 to 4 mol%. UV–vis spectra indicate that Zn ion doping caused a band gap decrease with increased doping of 0% to 4% Zn, respectively, from 5.15 eV for 4.96 eV. Samples with Zn in the crystal lattice showed better photocatalytic activity and degradation of the RhB dye after 16 min of UV exposureArtigo TiO2/PDMS nanocomposites for use on self-cleaning surfaces(Elsevier, 2014-01-25) Tavares, Marileide L.A.; Santos, Amélia S.F.; Santos, Ieda Maria Garcia dos; Silva, Manoel Rincón S.; Delmonte, Maurício Roberto Bomio; Silva, Elson Longo da; Paskocimas, Carlos Alberto; Motta, Fabiana Villela daIn this study, polydimethylsiloxane (PDMS)/TiO2 nanocomposite was processed by the spray method. TiO2 nanoparticles were synthesized by microwave-assisted hydrothermal method. Varying the proportion of nanoparticles in 0%, 0.5% and 1% by weight, commercial TiO2 (P25) was used for comparison purposes. The photocatalytic activity of nanocomposites impregnated with methylene blue was assessed by means of UV–visible spectroscopy. Changes in contact angle were analyzed before and after UV degradation tests. The effect of ultraviolet radiation on the chemical structure of the PDMS matrix was evaluated by Fourier transform infrared spectroscopy (FTIR). The results indicated that the addition of TiO2 nanoparticles in PDMS provides good photocatalytic properties in the decomposition of methylene blue, which is an important characteristic for the development of coatings for self-cleaning. For comparison purposes, commercial P25 was also used to investigate the photocatalytic activity