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Almacenamiento de hidrógeno reversible habilitado por luz de los borohidruros activados por vacíos fotogenerados
Xiaoyue Zhang1, Chaoqun Li1, Jikai Ye1
1Department of Materials Science, Fudan University, Shanghai 200433, China.
Journal of the American Chemical Society
|January 10, 2025
Resumen
Los investigadores desarrollaron un nuevo mecanismo inducido por la luz para liberar hidrógeno de los borohidruros a temperatura casi ambiente. Este método utiliza vacíos fotogenerados en hidrógeno de litio (LiH) para el almacenamiento eficiente de hidrógeno, logrando una capacidad de 11,02 wt % H2.
Área de la Ciencia:
- Ciencias de los materiales
- Química
- Almacenamiento de energía
Sus antecedentes:
- Los borohidruros ofrecen una alta densidad de hidrógeno para su almacenamiento, pero requieren altas temperaturas debido a su estabilidad.
- Los métodos actuales para la liberación de hidrógeno de los borohidruros consumen mucha energía.
Objetivo del estudio:
- Introducir un nuevo mecanismo de desestabilización inducida por la luz para el almacenamiento de hidrógeno en borohidritos.
- Para lograr la liberación de hidrógeno en condiciones ambientales mediante irradiación luminosa.
Principales métodos:
- Utilizó las vacantes fotogeneradas en hidruro de litio (LiH) para desestabilizar los enlaces B-H.
- Se emplean "reactores nano-fototérmicos" para una desestabilización y cinética optimizadas.
- Investigó LiBH4 como un sistema modelo para la liberación de hidrógeno inducida por la luz.
Principales resultados:
- Se consigue la liberación de hidrógeno a una temperatura cercana a la de la habitación, ~300 °C más baja que los métodos térmicos.
- Se ha demostrado una capacidad de almacenamiento de hidrógeno ultra elevada de 11,02% en peso de H2 en LiBH4.
- Demostró la aplicabilidad del mecanismo a otros borohidruros de metales alcalinos.
Conclusiones:
- La desestabilización inducida por la luz a través de vacantes fotogeneradas ofrece una vía de condiciones suaves para el almacenamiento de hidrógeno de boro.
- Los reactores nano-fototérmicos desarrollados mejoran la eficiencia y la capacidad.
- Este enfoque proporciona nuevos conocimientos para el desarrollo de materiales avanzados de almacenamiento de hidrógeno en estado sólido.
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