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Published on: June 7, 2018
Nanocables CoPt3 ferromagnéticos: evolución estructural desde el fcc hasta el ordenado L1(2)
Hao Ming Chen1, Chia Fen Hsin, Po Yuan Chen
1Department of Chemistry, National Taiwan University, Taipei 106, Taiwan.
Journal of the American Chemical Society
|October 8, 2009
Resumen
Las propiedades magnéticas de los nanocables de cobalto-platino (CoPt3) son mejoradas por una transición de fase inducida térmicamente. Esta transición de una aleación aleatoria a una estructura ordenada L1(2) mejora la coercitividad y la cuadratura.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
- El magnetismo es el magnetismo.
Sus antecedentes:
- Las aleaciones de cobalto-platino (CoPt3) son conocidas por sus propiedades magnéticas.
- Los materiales nanoestructurados ofrecen características físicas únicas.
- El control de las transiciones de fase es crucial para afinar las propiedades de los materiales.
Objetivo del estudio:
- Para investigar las propiedades magnéticas y las nanoestructuras de las matrices de alambre CoPt3 electrodeposited.
- Para entender la transición de fase que ocurre en los nanocables CoPt3.
- Para correlacionar la distribución atómica con el comportamiento magnético.
Principales métodos:
- Fabricación de matrices de alambre CoPt3 utilizando electrodeposición y plantillas de alumina porosa.
- Análisis de absorción de rayos X para estudiar las transiciones de fase.
- Mediciones de las propiedades magnéticas (coercividad, cuadratura).
Principales resultados:
- La absorción de rayos X confirmó una transición de fase en los nanocables CoPt3.
- La transición fue de una aleación aleatoria a una estructura CoPt3 (L1(2) ordenada anisotrópicamente.
- Esta transición de fase mejoró significativamente las propiedades magnéticas, incluida la coercitividad y la cuadratura.
Conclusiones:
- Se reveló un mecanismo de transición de fase inducido térmicamente en los nanocables CoPt3, que involucra un estado intermedio de "agrupación en agrupación" e interdifusión.
- Existe una fuerte correlación entre la distribución atómica y el carácter magnético de los nanocables CoPt3.
- Los hallazgos proporcionan información sobre el control de las propiedades magnéticas a través del ordenamiento estructural en nanocables.
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