DEMAT - Departamento de Engenharia de Materiais
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Article NiO-CGO Composite for SOFC Anode: Synthesis and Characterization(Journal of Materials Science and Engineering, 2010) Cela, Beatriz; Macedo, Daniel Araújo de; Souza, Graziele Lopes de; Miranda, Auristela Carla de; Martinelli, Antonio Eduardo; Nascimento, Rubens Maribondo do; Paskocimas, Carlos AlbertoArticle Avaliação da potencialidade de argilas do Rio Grande do Norte, Brasil. Parte-II: propriedades tecnológicas(Cerâmica Industrial, 2008) Dutra, Ricardo Peixoto Suassuna; Silva, Jaquelígia Brito da; Varela, Marcio Luiz; Nascimento, Rubens Maribondo do; Gomes, Uílame Umbelino; Paskocimas, Carlos AlbertoArticle Electrical conductivity and microstructure of NiO-CGO composites prepared by one-step synthesis(IOP Publishing, 2013-04-01) Nascimento, Rubens Maribondo do; Macedo, Daniel Araújo de; Figueiredo, Filipe Miguel Lebre; Patrício, Sónia Gonçalves; Martinelli, Antonio Eduardo; Paskocimas, Carlos Alberto; Marques, Fernando Manuel BicoThe correlation between the microstructure and electrical properties of NiO-Ce0.9Gd0.1O1.95 (NiO-CGO) composites prepared by a one-step synthesis method is reported in the present work, and compared to conventional samples synthesized by mechanically mixing commercial powders. Samples sintered between 1350 and 1450 °C had their microstructures and electrical properties investigated by scanning electron microscopy (SEM) and impedance spectroscopy. The total electrical conductivity in the range of 100 – 500 °C of one-step composites is more than one order of magnitude higher than for conventional material. This result is associated to the presence of a network of well-connected and homogeneously distributed NiO grains shown by SEM for the one-step composite, which is responsible for its improved percolative behavior and lower activation energy (0.24 eV at 250 – 650 °C).Article Síntese e caracterização de ferrita de níquel e níquel-zinco pelo método de polimerização de complexos(69° Congresso Anual da ABM - Internacional, 2014) Nascimento, Rubens Maribondo do; Assis, Raimison Bezerra de; Valcacer, Samara Melo; Silva, Camila Cruz da; Silva, Ariadne de Souza; Delmonte, Maurício Roberto Bomio; Paskocimas, Carlos Alberto; Gomes, Uílame Umbelino; Motta, Fabiana Villela daNickel-zinc ferrites are ferrimagnetic ceramic materials with cubic spinel type crystal structure, space group Fd3m belonging to being a solid solution composition of NiO, ZnO and Fe2O3. The complex polymerization method has enormous potential for obtaining magnetic ceramics, because it is a simple process, that originates from materials with high purity, which leads to obtaining powders with high chemical homogeneity and high surface area. This work aims to evaluate the structural and morphological characteristics of ferrites Ni0,25Zn0,75Fe2O4 and NiFe2O4 obtained by polymerization complex method. The solution was subjected to a final temperature of 120°C until the formation of the resin pyrolysed at a temperature of 350°C for 2 hours and calcined at 500°C for 2 hours. The resulting powders were characterized by X-ray diffraction (XRD), thermal analysis (TG/ DSC) and scanning electron microscopy (SEM). The results of XRD showed the formation of two compositions majority of ferrite phase. The results of SEM micrographs showed the formation of agglomerated particles with longitudinal plates to both compositions being important microstructural characteristics for magnetic application. The method of polymerization of complexes appeared as a promising method to obtain ceramic powders of nickel ferrite and nickel-zinc alloy for magnetic application.Article Citrate–hydrothermal synthesis, structure and electrochemical performance of La0.6Sr0.4Co0.2Fe0.8O3−δ cathodes for IT-SOFCs(Elsevier, 2013) Garcia, Laurênia Martins Pereira; Macedo, Daniel Araújo de; Souza, Graziele L.; Motta, Fabiana Villela da; Paskocimas, Carlos Alberto; Nascimento, Rubens Maribondo doArticle Comparação do desempenho da adição de carbonatos calcítico e dolomítico em massa cerâmica de revestimento queimada em forno industrial(Cubo, 2016) Nascimento, Rubens Maribondo do; Soares, R. A. L.; Castro, R. J. S.; Paskocimas, Carlos AlbertoArticle Photoluminescence properties of (Eu, Tb, Tm) co-doped PbMoO4 obtained by sonochemical synthesis(Elsevier, 2017-04-05) Gurgel, G. M.; Lovisa, Laura Ximena; Pereira, Laurenice Martins; Motta, Fabiana Villela da; Li, Maximo Siu; Silva, Elson Longo da; Paskocimas, Carlos Alberto; Delmonte, Maurício Roberto BomioArticle Structure, morphology and photoluminescence emissions of ZnMoO4: RE 3+=Tb3+ -Tm3+ - x Eu3+ (x = 1, 1.5, 2, 2.5 and 3 mol%) particles obtained by the sonochemical method(Elsevier, 2018-06-25) Lovisa, Laura Ximena; Oliveira, Marisa Carvalho de; Andrés, Juan; Gracia, Lourdes; Li, Maximo Siu; Silva, Elson Longo da; Tranquilin, Ricardo Luis; Paskocimas, Carlos Alberto; Delmonte, Maurício Roberto Bomio; Motta, Fabiana Villela daArticle Presence of excited electronic states on terbium incorporation in CaMoO4: Insights from experimental synthesis and first-principles calculations(Elsevier, 2021-02) Tranquilin, Ricardo Luis; Oliveira, Marisa Carvalho de; Santiago, Anderson de Azevedo Gomes; Lovisa, Laura Ximena; Ribeiro, Renan Augusto Pontes; Silva, Elson Longo da; Lazaro, Sergio R. de; Almeida, Cláudio Romero Rodrigues de; Paskocimas, Carlos Alberto; Motta, Fabiana Villela da; Delmonte, Maurício Roberto BomioArticle Ceramic crucibles: a new alternative for melting of PbO–BiO1.5–GaO1.5 glasses(Elsevier, 2002-07-10) Santos, Ieda Maria Garcia dos; Moreira, Rafael Carlos Martins; Souza, Antônio Gouveia de; Lebullenger, Ronan; Hernandes, Antônio Carlos; Leite, Edson Roberto; Paskocimas, Carlos Alberto; Silva, Elson Longo da