Structural and magnetic properties of Fe2-xCoSm xO4 - Nanoparticles and Fe2-xCoSm xO4 - PDMS magnetoelastomers as a function of Sm content

We have synthesized magnetic Fe2-xCoSmxO4 nanoparticles (NPs) by means of the coprecipitation method, varying Sm content from x=0 to x=0.5. Energy-dispersive X-ray spectroscopy showed agreement between the metal proportion of the obtained nanoparticles and the stoichiometric mixture of cations used...

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Detalhes bibliográficos
Autores: Ruiz, Mariano M., Mietta, José L., Antonel, Paula Soledad, Pérez, Oscar E., Martín Negri, R., Jorge, Guillermo Antonio
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2013
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositório:CONICET Digital (CONICET)
Idioma:inglês
OAI Identifier:oai:ri.conicet.gov.ar:11336/180710
Acesso em linha:http://hdl.handle.net/11336/180710
Access Level:Acceso aberto
Palavra-chave:MAGNETIC COMPOSITES
MAGNETIC NANOPARTICLES
MAGNETOELASTOMERS
MAGNETORHEOELASTOMERS
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descrição
Resumo:We have synthesized magnetic Fe2-xCoSmxO4 nanoparticles (NPs) by means of the coprecipitation method, varying Sm content from x=0 to x=0.5. Energy-dispersive X-ray spectroscopy showed agreement between the metal proportion of the obtained nanoparticles and the stoichiometric mixture of cations used for the synthesis. Part of the particles were heated at 800 °C, and both were characterized by X-ray diffraction, scanning electron microscope imaging and magnetization measurements. Physical and magnetic properties were analyzed as a function of Sm content, before and after the heating treatment. A phase segregation is found for the calcined nanoparticles with large Sm content. The magnetic remanence, saturation and coercive field were investigated as a function of Sm content for both heated and unheated (as-prepared) particles. Polydimethylsiloxane-NPs magnetoelastomers were prepared and cured under an external uniform magnetic field, obtaining structured anisotropic composites, in which inorganic needles (columnar micrometric structures) oriented in the direction of the magnetic field are formed. Young modulus and remanent magnetic moment were measured and magnetization time relaxation experiments were performed in the directions parallel and perpendicular to the needles in order to determine the magnetic and elastic anisotropy of the composites. The elastic modulus measured parallel to the needles resulted almost twice in magnitude with respect to the perpendicular modulus. The measured magnetic anisotropy of the composites is probably due to the enhanced interparticle interaction within a needle and the freezing of an preferred easy axis distribution among the particles at the curing process.