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Control de la estructura cristalina de las nanopartículas de aleación de solución sólida binaria y ternaria con una
Quan Zhang1, Kohei Kusada1, Dongshuang Wu1
1Division of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
Journal of the American Chemical Society
|February 23, 2022
Resumen
Las nanopartículas de aleación hexagonales compactas (hcp) exhiben una actividad catalítica superior para la evolución del hidrógeno en comparación con las fases cúbicas centradas en la cara (fcc). Este estudio demuestra la síntesis controlada de aleaciones de hcp y fcc, revelando hcp-RuIrPt
Área de la Ciencia:
- Ciencias de los materiales
- Nanotecnología
- Catálisis
Sus antecedentes:
- La estructura cristalina influye críticamente en las propiedades del estado sólido.
- El control de la estructura cristalina de la aleación en una composición fija es un desafío.
- Las propiedades dependientes de la estructura del cristal de la aleación están poco exploradas.
Objetivo del estudio:
- Para sintetizar nanopartículas de aleación Ru-Pt, Ru-Ir y Ru-Ir-Pt con estructuras cristalinas hexagonales cerradas (hcp) y cúbicas centradas en la cara (fcc).
- Investigar el impacto de la estructura cristalina en el rendimiento catalítico de estas nanopartículas de aleación.
- Explorar el potencial de las aleaciones de HCP para mejorar la electrocatálisis.
Principales métodos:
- Método de reducción química para la síntesis de nanopartículas de aleación.
- Ajuste preciso de las velocidades de reducción de precursores metálicos para controlar la estructura del cristal.
- Pruebas electrocatalíticas para la reacción de evolución del hidrógeno (HER) en medios alcalinos.
Principales resultados:
- Síntesis exitosa de nanopartículas de aleación en solución sólida binarias (Ru-Pt, Ru-Ir) y ternales (Ru-Ir-Pt) con fases controlables de hcp y fcc.
- Todas las nanopartículas de aleación de hcp sintetizadas demostraron una actividad electrocatalítica superior para HER en comparación con sus contrapartes fcc.
- Hcp-RuIrPt exhibió una actividad intrínseca y de masa significativamente mejorada (3,1-6,9 veces) en comparación con fcc-RuIrPt y Pt/C comercial.
Conclusiones:
- Se puede lograr un control preciso de la estructura cristalina de la aleación a través de la velocidad de reducción.
- La estructura cristalina hcp mejora la actividad electrocatalítica para la reacción de evolución del hidrógeno en aleaciones.
- Hcp-RuIrPt representa un catalizador muy prometedor para la producción eficiente de hidrógeno.
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