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Un electrocatalizador sintético de níquel con una frecuencia de rotación superior a 100.000 s−1 para la producción de
Monte L Helm1, Michael P Stewart, R Morris Bullock
1Center for Molecular Electrocatalysis, Chemical and Materials Sciences Division, Pacific Northwest National Laboratory, Post Office Box 999, K2-57, Richland, WA 99352, USA.
Science (New York, N.Y.)
|August 13, 2011
Resumen
Los científicos han desarrollado un nuevo catalizador de complejo de níquel para la producción eficiente de hidrógeno (H2O) a partir de ácidos. Este avance ofrece una alternativa rentable al platino para aplicaciones de almacenamiento de energía.
Área de la Ciencia:
- La catálisis de la catálisis.
- Ciencia de los materiales Ciencia de los materiales.
- Almacenamiento de energía Almacenamiento de energía
Sus antecedentes:
- Los catalizadores a base de platino son efectivos para la producción de hidrógeno, pero están limitados por el costo y la escasez.
- Las enzimas biológicas de la hidrogenasa utilizan metales abundantes en la tierra como el hierro y el níquel para una eficiente generación de H2O.
- El desarrollo de catalizadores sintéticos con una eficiencia similar utilizando materiales abundantes es crucial para la energía sostenible.
Objetivo del estudio:
- Para investigar un complejo de níquel sintético como catalizador para la producción de hidrógeno.
- Para evaluar la eficiencia catalítica y el mecanismo del complejo de níquel utilizando dimetilformamida protonada.
- Explorar el potencial de los catalizadores metálicos abundantes en la tierra para el almacenamiento de energía.
Principales métodos:
- Síntesis y caracterización de un nuevo complejo de níquel: [Ni (((P (((Ph)) (((2) N (((Ph)) ((2)) ] (((BF ((4))) (((2).
- Producción de hidrógeno electrocatalítico utilizando dimetilformamida protonada como fuente de protones.
- Medición de las frecuencias de rotación (s(-1)) en acetonitrilo con y sin agua.
- Análisis electroquímico a un potencial de -1.13 V frente al ferrocenio/ferroceno.
Principales resultados:
- El complejo de níquel sintético demostró una alta actividad catalítica para la producción de H2O.
- Las frecuencias de rotación alcanzaron 33.000 s(-1) en acetonitrilo seco y 106.000 s(-1) con 1,2 M de agua.
- El catalizador funcionó a un potencial bajo de -1.13 V, lo que indica la eficiencia.
- Los estudios mecánicos sugirieron un papel para las aminas colgantes que actúan como relés de protones.
Conclusiones:
- Un complejo de níquel sintético cataliza eficientemente la producción de hidrógeno, ofreciendo una alternativa prometedora al platino.
- Las altas frecuencias de rotación resaltan el potencial de los catalizadores metálicos abundantes en la tierra para el almacenamiento de energía.
- El mecanismo propuesto que involucra aminas colgantes proporciona información sobre el diseño de futuros catalizadores.
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