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Aleación Pd-Pt a nivel atómico y gran mejora de la capacidad de almacenamiento de hidrógeno en nanopartículas
Hirokazu Kobayashi1, Miho Yamauchi, Hiroshi Kitagawa
1Department of Chemistry, Faculty of Science, Kyushu University, Hakozaki, Fukuoka 812-8581, Japan.
Journal of the American Chemical Society
|April 6, 2010
Resumen
Los investigadores crearon nuevas nanopartículas de solución sólida de paladio-platino (Pd-Pt) con almacenamiento de hidrógeno mejorado. Esta mezcla a nivel atómico aumenta significativamente la capacidad de hidrógeno, ajustable por composición.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
- Química Física es la química física.
Sus antecedentes:
- Las nanopartículas de núcleo-capa son típicamente sintetizadas con capas distintas.
- Lograr una mezcla atómica homogénea en las nanopartículas de aleación presenta desafíos de síntesis.
- Los materiales de almacenamiento de hidrógeno requieren propiedades eficientes y sintonizables.
Objetivo del estudio:
- Desarrollar un método para crear nanopartículas homogéneas de solución sólida de paladio-platino (Pd-Pt).
- Investigar la transformación estructural de las estructuras de núcleo-capa a las estructuras de solución sólida.
- Para evaluar la capacidad de almacenamiento de hidrógeno de las nanopartículas de solución sólida Pd-Pt sintetizadas.
Principales métodos:
- Síntesis de las nanopartículas de núcleo (Pd) /caparazón (Pt).
- El desencadenamiento de la transformación estructural a través de ciclos de absorción/desorción de hidrógeno.
- Caracterización utilizando difracción de rayos X en polvo in situ, espectros de dispersión de energía, RMN de estado sólido (2) H y isotermas de composición por presión de hidrógeno.
Principales resultados:
- Mezcla atómica homogénea de Pd y Pt lograda en nanopartículas en solución sólida.
- Transformación estructural confirmada por múltiples técnicas avanzadas de caracterización.
- Las nanopartículas Pd-Pt en solución sólida (8-21 átomos % Pt) exhibieron una mayor capacidad de almacenamiento de hidrógeno que las nanopartículas Pd puras.
- La capacidad de almacenamiento de hidrógeno era ajustable ajustando la composición de Pd y Pt.
Conclusiones:
- La absorción/desorción de hidrógeno es un disparador eficaz para la creación de nanopartículas Pd-Pt en solución sólida.
- Las nanopartículas de solución sólida Pd-Pt resultantes ofrecen propiedades superiores de almacenamiento de hidrógeno en comparación con las estructuras tradicionales de núcleo de cáscara.
- La composición sintonizable permite optimizar el rendimiento de almacenamiento de hidrógeno en las nanopartículas de aleación Pd-Pt.
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