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Electrocatalizadores ternales para la oxidación del etanol a dióxido de carbono: haciéndolos capaces de dividir
Meng Li1, David A Cullen, Kotaro Sasaki
1Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973, United States.
Journal of the American Chemical Society
|December 6, 2012
Resumen
Los investigadores descubrieron que el iridio (Ir) puede romper los enlaces carbono-carbono en la electrooxidación del etanol (EOR) cuando se combina con el óxido de platino y el estaño. Este hallazgo avanza la oxidación eficiente del etanol a CO2 a temperatura ambiente.
Área de la Ciencia:
- La electroquímica es electroquímica.
- Ciencia de los materiales Ciencia de los materiales.
- La catálisis es la catálisis.
Sus antecedentes:
- La división del enlace carbono-carbono es un gran desafío en la electrooxidación del etanol (EOR) a CO2.
- Trabajos anteriores identificaron un electrocatalisador ternario PtRhSnO2 capaz de la escisión de enlaces C-C a temperatura ambiente.
Objetivo del estudio:
- Investigar si el iridio (Ir) también puede facilitar la división de enlaces C-C en electrocatalizadores ternales para EOR.
- Para sintetizar y caracterizar los electrocatalizadores de las nanoislas multimetales en un núcleo de nanopartículas SnO2.
Principales métodos:
- Síntesis de electrocatalizadores de nanopartículas con soporte de carbono con nanoislas multimetales (PtIr, PtRh, IrRh, PtIrRh) en un núcleo SnO2 utilizando un enfoque de crecimiento sembrado.
- Caracterización utilizando diversas técnicas para determinar la composición y la arquitectura.
- Estudios electroquímicos y espectroscopia de absorción de reflexión infrarroja in situ para evaluar la actividad y los intermediarios de reacción.
Principales resultados:
- Varios electrocatalizadores sintéticos multimetales/SnO2/C exhibieron una reactividad EOR y una selectividad hacia el CO2 significativamente más altas en comparación con los Pt/C y Pt/SnO2/C. convencionales.
- El catalizador PtIr / SnO2 / C, particularmente con alto contenido de Ir, demostró un rendimiento excepcional, incluido el potencial de inicio de EOR más negativo.
- La evidencia sugiere que Ir, al igual que Rh, puede dividir efectivamente el enlace C-C en el sistema ternario.
Conclusiones:
- El iridio puede ser inducido a dividir el enlace C-C como componente de un electrocatalizador ternario para la electrooxidación del etanol.
- El catalizador PtIr/SnO2/C muestra un potencial prometedor para una eficiente oxidación completa del etanol a CO2.
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