ELIANE CARMO OLIVEIRA
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Resumo IPEN-doc 25476 UV–Vis photocatalytic performance of the S-doped TiO2 and TiO2 thin films for water treatment2018 - BENTO, R.T.; SZURKALO, M.; OLIVEIRA, E.C.; CORREA, O.V.; PILLIS, M.F.TiO2 films have been widely used as catalysts in oxidative processes in order to degrade organic contaminant. However, without the presence of a dopant material, its photocatalytic activity is limited only in the region of ultraviolet radiation (UV), due to its high-energy band gap. In this present research, anatase TiO2 thin films were grown on borosilicate substrates by metalorganic chemical vapor deposition (MOCVD) at 400ºC. To make the semiconductor active in the visible light region, sulfur doped TiO2 films were prepared by means of a thermochemical treatment carried out in a tubular oven, under atmosphere of H2S at 50ºC for 60 minutes. The films were characterized by XRD, AFM, FE-SEM and XPS technique. The photocatalytic behavior of the films was evaluated by methyl orange dye degradation under UV-Vis irradiation for 300 minutes. The photocatalytic tests were realized in a reactor illuminated by two tubular UV lamps (352 nm), and in a reactor illuminated by visible light (400-700 nm) on different intensities, both containing 40 mL of the dye solution. The results showed that the S-TiO2 films present promising photocatalytic efficiency. Without the presence of the catalyst, there was no degradation of the methyl orange dye under UV-Vis irradiation. Non-doped TiO2 films do not exhibited photocatalytic activity under visible light. It was possible to observe that the visible light intensity influences the doped films photocatalytic performance.Artigo IPEN-doc 20788 Study of electrical, mechanical and microstructural properties of composites based on Cu-Ni-Ag-Alsub(2)Osub(3) obtained by powder metallurgy2014 - MONTEIRO, WALDEMAR A.; CARRIO, JUAN A.G.; OLIVEIRA, E.C.; PREVIATTI, G.G.; SILVA, L.C.E.The synthesis, microstructural, electrical and mechanical properties characterization of composites based on Cu-Ni–Ag-Al2O3 is a work that exposes the investigation of the correlation of the microstructures formed in the material with its physical properties and its manufacturing method. Cermets based on copper, nickel and silver have been doped with alumina varying the proportions of these components to create, by powder metallurgy, a material that has good electrical conductivity and good mechanical strength compared with that of pure copper, together with a manufacturing process which is both cost and energy efficient. The conductivity values vary between 30 to 55% IACS showing that the thermal treatments were effective for electrical connector uses.