Centro de Tecnologia
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Article The effect of particle size on structural and catalysts for oxygen evolution reaction of (CoFeNiMnCr)3O4 prepared by controlled synthesis with polyvinylpyrrolidone (PVP)(Journal of Colloid and Interface Science, 2025-02-15) Gomes, Uilame Umbelino; Alves, Ricardo Francisco; Raimundo, Rafael Alexandre; Lima, Bruno Alessandro Silva Guedes de; Loureiro, Francisco José Almeida; Fagg, Duncan Paul; Macedo, Daniel Araújo de; Morales, Marco Antonio; https://orcid.org/0000-0002-4074-0762; https://orcid.org/0000-0001-8958-7263; https://orcid.org/0000-0002-9943-9464; https://orcid.org/0000-0003-4966-7140; https://orcid.org/0000-0002-5050-3859; https://orcid.org/0000-0001-6287-9223; https://orcid.org/0000-0003-0466-1458; https://orcid.org/0000-0002-3098-5731Article Structural, magnetic and electrocatalytic properties of rock salt oxide nanofibers (Ni0.2Mg0.2Zn0.2Cu0.2-xCo0.2+x)O produced by air-heated solution blow spinning (A-HSBS) for oxygen evolution reaction(Applied Surface Science, 2025-02-15) Gomes, Uilame Umbelino; Oliveira Filho, Ronaldo M.; Alves, Ricardo Francisco; Raimundo, Rafael Alexandre; Hortêncio, Johnnys da Silva; Lopes, Caio Matheus Sousa; Nascimento, Emanuel Pereira; Araújo, Allan Jedson Menezes de; Loureiro, Francisco José Almeida; Medeiros, Eliton Souto de; Morales, Marco Antonio; Macedo, Daniel Araújo de; Menezes, Romualdo Rodrigues; https://orcid.org/0000-0002-4074-0762; https://orcid.org/0000-0001-8958-7263; https://orcid.org/0000-0002-9943-9464; https://orcid.org/0000-0002-4028-5499; https://orcid.org/0000-0003-1294-8897; https://orcid.org/0009-0002-9856-9846; https://orcid.org/0000-0003-0386-9329; https://orcid.org/0000-0002-5050-3859; https://orcid.org/0000-0002-9033-9141; https://orcid.org/0000-0002-3098-5731; https://orcid.org/0000-0003-0466-1458; https://orcid.org/0000-0003-4316-2168Article Synthesis and characterization of (Fe0.2Ni0.2Co0.2Al0.2Zn0.2)3O4 high entropy oxide as electrocatalyst for oxygen evolution reaction(Journal of Alloys and Compounds, 2025-04-10) Gomes, Uílame Umbelino; Vasconcelos, Gabrel dos Santos; Raimundo, Rafael Alexandre; Lima, Maria José Santos; Arújo, Kívia Fabiana Galvão; Silva, Matheus Duarte da; Macedo, Daniel Araújo de; Karimi, Meysam Mashhadikarimieysam; Huaman, Raquel Checca; Gastelois, Pedro Lana; Morales, Marco Antonio; https://orcid.org/0009-0008-6974-9630; https://orcid.org/0000-0002-9943-9464; https://orcid.org/0000-0001-8957-9204; https://orcid.org/0000-0002-7197-2582; https://orcid.org/0000-0003-0466-1458; https://orcid.org/0000-0003-1449-3654; https://orcid.org/0000-0002-8898-2584; https://orcid.org/0000-0001-7849-5013; https://orcid.org/0000-0002-3098-5731Article 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 One-step synthesis of composite electrolytes of Eu-doped ceria and alkali metal carbonates(Elsevier, 2013-12-13) Nascimento, Rubens Maribondo do; Rajesh, Surendran; Macedo, Daniel Araújo de; Souza, Graziele Lopes de; Figueiredo, Filipe Miguel Henriques Lebre Ramos; Marques, Fernando M. B.Article 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 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 Cobalt-free perovskite Pr0.5Sr0.5Fe1 xCuxO3 d(PSFC) as a cathodematerial for intermediate temperature solid oxide fuel cells(Elsevier, 2016-09-01) Nascimento, Rubens Maribondo do; Moura, Caroline Gomes; Fagg, Duncan Paul; Grilo, João Paulo de Freitas; Macedo, Daniel Araújo de; Cesário, Moises RômolosArticle Effect of composition on the structural development and electrical conductivity of NiO-GDC composites obtained by one-step synthesis(Elsevier, 2017-08) Nascimento, Rubens Maribondo do; Grilo, João Paulo de Freitas; Moura, Caroline Gomes; Macedo, Daniel Araújo de; Rajesh, Surendran; Figueiredo, Filipe M. L.; Marques, Fernando M. B.Article One-step synthesis and microstructure of CuO-SDC composites(FapUNIFESP (SciELO), 2017-03) Nascimento, Rubens Maribondo do; Firmino, Hellen Cristina Torrano; Araújo, A. J. M.; Dutra, Ricardo P. S.; Rajesh, Surendran; Macedo, Daniel Araújo deUma rota de síntese em uma etapa baseada no método dos precursores poliméricos foi usada para produzir pós do nanocompósito contendo as fases CuO e céria dopada com samária (SDC). Esta rota química permitiu obter pós compósitos com reduzido tamanho de partícula e uniforme distribuição dos elementos Cu, Ce e Sm. O material particulado foi caracterizado por difração de raios X (DRX) combinado com refinamento Rietveld dos dados de difração. Compósitos CuO-SDC sinterizados em ar entre 950 e 1050 °C e em seguida reduzidos a Cu-SDC foram caracterizados por DRX e microscopia eletrônica de varredura. A porosidade aberta foi medida usando o princípio de Arquimedes. Microestruturas adequadas para os processos de transferência de carga e transporte de massa (30 a 45% de porosidade) foram obtidas em cermets Cu-SDC previamente sinterizados a 1000 a 1050 °C. Os resultados indicaram que compósitos CuO-SDC e cermets Cu-SDC com potencial aplicação como anodos de células a combustível de óxido sólido (CCOS) podem ser obtidos por projeto microestrutural. Meia célula suportada no anodo foi preparada por coprensagem e cossinterização de céria dopada com gadolínia (CGO) e o nanocompósito obtido neste trabalho