Navegação Ciências Exatas e da Terra por Autor "Teixeira, Sergio Ribeiro"

Resultados 21-32 de 32

    • Photoelectrochemical study of Ta3N5 nanotubes for water splitting 

      Khan, Sherdil; Santos, Marcos José Leite; Dupont, Jairton; Teixeira, Sergio Ribeiro (2014) [Artigo de periódico]
      Nanotubes (NTs) of Ta3N5 were synthesized by nitridation of Ta2O5 NTs. The samples were studied by scanning electron microscopy, UV-VIS spectrophotometry, x-ray diffraction and photoelectrochemical (PEC) measurements carried ...

    • Photosensitised degradation of organic dyes by visible light using riboflavin adsorbed on the surface of TiO2 nanotubes 

      Backes, Cláudio Cesar Weber; Scheffer, Francine Ramos; Pereira, Marcelo Barbalho; Teixeira, Sergio Ribeiro; Weibel, Daniel Eduardo (2014) [Artigo de periódico]
      A degradação de soluções aquosas de índigo carmim (IC), azul de metileno (MB) e laranja de metilo (MO) assistida pela luz visível foi conseguida sobre a superfície de nanotubos (NTs) de TiO2 impregnados com riboflavina ...

    • Polypyrrole/ionic liquid/Au nanoparticle counter-electrodes for dye-sensitized solar cells : improving charge-transfer resistance at the CE/electrolyte interface 

      Loguercio, Lara Fernandes; Matos, Carolina Ferreira de; Oliveira, Matheus Costa de; Marin, Graciane; Khan, Sherdil; Dupont, Jairton; Teixeira, Sergio Ribeiro; Balzaretti, Naira Maria; Ferreira, Jacqueline; Santos, Marcos José Leite (2019) [Artigo de periódico]
      To provide a viable alternative for counter electrodes used in dye sensitized solar cells, polypyrrole (PPy) based films have been synthesized via electrochemical deposition in the presence of the ionic liquid 1-butyl-3- ...

    • Ruthenium dioxide nanoparticles in ionic liquids : synthesis, caracterization and catalytic properties in hydrogenation of olefins and arenes 

      Rossi, Liane Marcia; Dupont, Jairton; Machado, Giovanna; Fichtner, Paulo Fernando Papaleo; Radtke, Claudio; Baumvol, Israel Jacob Rabin; Teixeira, Sergio Ribeiro (2004) [Artigo de periódico]
      A reação de NaBH4 com RuCl3 dissolvido no líquido iônico 1-n-butil-3-metilimidazólio hexafluorfosfato (BMI.PF6) é um método simples e reprodutível para a síntese de nanopartículas de RuO2 estáveis com distribuição estreita ...

    • Structural change and heteroepitaxy induced by rapid thermal annealing of CaF/sub 2/ films on Si(111) 

      Mattoso Filho, Ney Pereira; Mosca Junior, Dante Homero; Schreiner, Wido Herwig; Mazzaro, Irineu; Teixeira, Sergio Ribeiro; Macedo, Waldemar A.A.; Martins, M.D. (1998) [Artigo de periódico]
      In this article we show that heteroepitaxial CaF2 films can be induced on Si~111! with a rapid thermal anneal. The change from preferentially oriented polycrystals to a single crystal with type- B epitaxy is visible by ...

    • Structural changes of fe precipitates in annealed fe-al/sub 2/o/sub 3/ films 

      Alves, Maria do Carmo Martins; Tolentino, Hélio Cesar Nogueira; Teixeira, Sergio Ribeiro; Flores, Wladimir Hernandez; Boff, Marco Aurelio Silveira; Casarin, Fabricio de Oliveira; Schmidt, Joao Edgar (1999) [Artigo de periódico]
      We report on the structural changes of Fe-AI203 films deposited - both co-evaporated and multilayered samples - at room temperature and subsequently annealed at 400"C during 5h. Our results suggest that the Fe precipitates ...

    • Structural modifications in FexCo1-x/Cu multilayers induced by ion irradiation 

      Graff, Ismael Leandro; Teixeira, Sergio Ribeiro; Amaral, Livio; Alves, Maria do Carmo Martins; Flores, Wladimir Hernandez (2004) [Artigo de periódico]
      The structural evolution of Fe30Co70 /Cu multilayers under ion irradiation is investigated in detail using x-ray techniques. The samples were irradiated with two different ions, 50 keV of He+ and 600 keV of Kr+, at room ...

    • The epitaxial growth of evaporated cu/caf2 bilayers on si(111) 

      Mattoso Filho, Ney Pereira; Mosca Junior, Dante Homero; Mazzaro, Irineu; Teixeira, Sergio Ribeiro; Schreiner, Wido Herwig (1995) [Artigo de periódico]
      Successful and unexpected epitaxial growth of Cu/CaF2, bilayers on hydrogen terminated Si(111) wafers by thermal evaporation is reported. The bilayers were characterized with conventional x-ray diffraction experiments, ...

    • The evolution of sputtered iron nitride thin films under thermal treatment 

      Monteiro, W.A.; Schreiner, Wido Herwig; Baumvol, Israel Jacob Rabin; Dionisio, Paulo Henrique; Teixeira, Sergio Ribeiro; Mosca Junior, Dante Homero (1991) [Artigo de periódico]
      The thermal evolution of reactively sputtered iron nitride thin films has been investigated by xray diffraction, Mössbauer conversion electron spectroscopy, transmission electron microscopy, and magnetic measurementsT. he ...

    • The influence of aluminum grain size on alumina nanoporous structure 

      Feil, Adriano Friedrich; Costa, Marlla Vallerius da; Amaral, Livio; Teixeira, Sergio Ribeiro; Migowski, Pedro; Dupont, Jairton; Machado, Giovanna; Peripolli, Suzana Bottega (2010) [Artigo de periódico]
      An approach to control the interpore distances and nanopore diameters of 150-nm-thick thin aluminum films is reported here. The Al thin films were grown by sputtering on p-type silicon substrate and anodized with a ...

    • Third-order nonlinear optical response of colloidal gold nanoparticles prepared by sputtering deposition 

      Castro, Hermerson Pablo Silva; Santos, Heberton Wender Luiz dos; Alencar, Marcio André Rodrigues Cavalcanti de; Teixeira, Sergio Ribeiro; Dupont, Jairton; Hickmann, Jandir Miguel (2013) [Artigo de periódico]
      The nonlinear optical responses of gold nanoparticles dispersed in castor oil produced by sputtering deposition were investigated, using the thermally managed Z-scan technique. Particles with spherical shape and 2.6 nm of ...

    • X-ray-absorption spectroscopy and x-ray diffraction in discontinuous Co/sub x/Fe/sub 1-x//Ag multilayers 

      Flores, Wladimir Hernandez; Teixeira, Sergio Ribeiro; Cunha, Joao Batista Marimon da; Alves, Maria do Carmo Martins; Tolentino, Hélio Cesar Nogueira; Traverse, Agnes (2000) [Artigo de periódico]
      This paper reports on the structural properties of CoxFe12x /Ag discontinuous multilayers with x 50, 0.3, 0.7, and 1. The evolution of the structural properties has been investigated by x-ray diffraction and x-ray-absorption ...