Size-Dependent passivation shell and magnetic properties in antiferromagnetic/ferrimagnetic core/shell MnO nanoparticles

The magnetic properties of bimagnetic core/shell nanoparticles consisting of an antiferromagnetic MnO core and a ferrimagnetic passivation shell have been investigated. It is found that the phase of the passivation shell (γ-Mn2O3 or Mn3O4) depends on the size of the nanoparticles. Structural and mag...

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Detalles Bibliográficos
Autores: López-Ortega, Alberto, Tobia, Dina, Winkler, Elin, Golosovsky, Igor V., Salazar-Alvarez, German, Estradé Albiol, Sònia, Estrader i Bofarull, Marta, Sort, Jordi, González, Miguel, Suriñach, Santiago (Suriñach Cornet), Arbiol i Cobos, Jordi, Peiró Martínez, Francisca, Zysler, Roberto D., Baró, M. D., Nogués, Josep
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2010
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/176672
Acceso en línea:https://hdl.handle.net/2445/176672
Access Level:acceso abierto
Palabra clave:Nanopartícules
Propietats magnètiques
Nanoparticles
Magnetic properties
Descripción
Sumario:The magnetic properties of bimagnetic core/shell nanoparticles consisting of an antiferromagnetic MnO core and a ferrimagnetic passivation shell have been investigated. It is found that the phase of the passivation shell (γ-Mn2O3 or Mn3O4) depends on the size of the nanoparticles. Structural and magnetic characterizations concur that while the smallest nanoparticles have a predominantly γ-Mn2O3 shell, larger ones have increasing amounts of Mn3O4. A considerable enhancement of the Néel temperature, TN, and the magnetic anisotropy of the MnO core for decreasing core sizes has been observed. The size reduction also leads to other phenomena such as persistent magnetic moment in MnO up to high temperatures and an unusual temperature behavior of the magnetic domains.