EVERTON BONTURIM
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Resumo IPEN-doc 24604 Nuclear based techniques in multifunctional materials characterization2017 - BONTURIM, E.; MAZZOCCHI, V.L.; PARENTEA, C.B.R.; MOREIRA, E.G.; SEO, E.S.M.; FELINTO, M.C.F.C.The Nuclear Science and its technologies have provided fundamental tools for the understanding of new chemical and physical properties that help the development of the new age of multifunctional materials such as the Perovskites for photovoltaics and fuel cells, the luminescent oxides for lighting and biomarkers and the thin films in semiconductors. One of the most important parameters that defines key properties of the Perovskites to be applied as the cathode in fuel cells is their crystal structure and its point defects (e.g. oxygen vacancies), which can be determined by neutron diffraction (Fig. 1a). Photonic materials like luminescent nanoparticles, once doped with Rare Earth ions, they can emit light when excited with UV/IR, being used in probing bioassays. In this case, the precise determination of Rare Earth concentration by Instrumental Neutron Activation Analysis (INAA) leads to ensure the desired spectroscopy properties to prepare efficient probing nanoparticles (Fig.1b). Furthermore, nuclear based techniques such as Rutherford Backscattering Spectrometry (RBS) help us in determining the thickness and the elemental composition of thin films (Fig. 1c), which is not usually easy through other conventional techniques. In other words, the nuclear based techniques applied on materials characterization play a key role in providing a solid understanding on the physical and chemical properties of the condensed matter. In summary, this work presents three cases where the use of the Nuclear Techniques improves the characterization of different materials. All the data shown here were collect and published somehow, as indicated below.Artigo IPEN-doc 21301 Oxygen stoichiometry of Basub(0.50)Srsub(0.50)Cosub(0.80)Fesub(0.20)Osub(3-'delta') obtained by EDTA-citrate method and measured by X-ray and neutron diffraction2015 - BONTURIM, EVERTON; MAZZOCCHI, VERA L.; PARENTE, CARLOS B.R.; MESTNIK FILHO, JOSE; LIMA, NELSON B. de; SEO, EMILIA S.M.The compound Ba0.50Sr0.50Co0.80Fe0.20O3–d (BSCF) has been used as a good candidate for air electrodes in Intermediate Temperature Solid Oxide Fuel Cells. Present work deals with the oxygen vacancy of this compound synthesized by using the EDTA–Citrate method. To obtain a single-phase sample, three portions of the compound were calcined at 700, 800 and 900 C. Only the sample calcined at 900 C showed a single phase. The stoichiometry of the single-phase sample, in particular of the oxygen atom, was determined by applying the combined X-ray and neutron Rietveld refinement to X-ray and neutron powder diffraction patterns measured with the sample.Resumo IPEN-doc 20386 Crystalline structure and oxigen stoichiometry of the Ba0.50Sr0.50Co0.80Fe0.20O3-d powders obtained by EDTA-Citrate method measured by X-ray and neutron diffraction2014 - BONTURIM, EVERTON; LIMA, NELSON B. de; MAZZOCCHI, VERA L.; PARENTE, CARLOS B.R.; MESTNIK FILHO, JOSE; SEO, EMILIA S.M.