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A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions
Published on: August 17, 2016
Enlace dihidrógeno homopolar en amidoboranos de metales alcalinos y sus implicaciones para el almacenamiento de
David J Wolstenholme1, James T Titah, Franklin N Che
1Department of Chemistry, University of New Brunswick, P.O. Box 4400, Fredericton, New Brunswick E3B 5A3, Canada. dwolsten@unb.ca
Journal of the American Chemical Society
|August 24, 2011
Resumen
Una nueva investigación revela interacciones ocultas hidrógeno-hidrógeno en litio y amida de sodio borohidruro. Estas interacciones homopolares, junto con las polares conocidas, mejoran la estabilidad de estos materiales cristalinos.
Área de la Ciencia:
- Química del estado sólido.
- Ciencia de los materiales ciencia de los materiales.
- Materiales de almacenamiento de hidrógeno materiales de almacenamiento de hidrógeno.
Sus antecedentes:
- El borohidruro de amida de litio (LiNH2BH3) y el borohidruro de amida de sodio (NaNH2BH3) son materiales cristalinos con aplicaciones potenciales en el almacenamiento de hidrógeno.
- Estudios anteriores identificaron interacciones polares (M··H-B y N-H··H-B) dentro de sus estructuras de estado sólido.
Objetivo del estudio:
- Investigar la presencia y la importancia de las interacciones homopolares hidrógeno-hidrógeno en LiNH2BH3 y NaNH2BH3.3.
- Comprender la contribución de estas interacciones a la estabilidad estructural general y a las vías de descomposición térmica.
Principales métodos:
- Análisis de las estructuras cristalinas de estado sólido.
- Espectroscopia de resonancia magnética nuclear (RMN) en el isótopo LiND2BH3.3.
Principales resultados:
- Identificación de las interacciones homopolares previamente pasadas por alto: B-H···H-B y N-H···H-N.
- Estas interacciones homopolares contribuyen significativamente a la estabilidad de las estructuras cristalinas extendidas.
- El estudio de RMN indica desorción térmica de H2 y HD, lo que sugiere interacciones hidruro-hidruro directas o indirectas durante la descomposición.
Conclusiones:
- Las interacciones hidrógeno-hidrógeno homopolares son cruciales para comprender la estabilidad estructural de LiNH2BH3 y NaNH2BH3.
- Estas interacciones juegan un papel en los mecanismos de descomposición térmica, influyendo en la liberación de hidrógeno.
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