Thermal decomposition of alkaline-earth metal hydride and ammonia borane composites
Abstract
We demonstrate a method to improve the promising hydrogen storage capabilities of ammonia borane by making composites with alkaline-earth metal hydrides using ball-milling technique. The ball-milling for the mixtures of alkaline-earth metal hydride (MgH 2 or CaH 2) and ammonia borane (AB) yields a destabilization compared with the ingredient of the mixture, showing the hydrogen capacity of 8.7 and 5.8 mass% at easily accessible dehydrogenation peak temperatures of 78 and 72 °C, respectively, without the unwanted by-product borazine. Through detailed analyses on the dehydrogenation performance of the composite at various ratios in the hydride and AB, we proposed a different chemical activation mechanism from that in the LiH/AB and NaH/AB systems reported in a previous literature.
- Publication:
-
International Journal of Hydrogen Energy
- Pub Date:
- January 2010
- DOI:
- 10.1016/j.ijhydene.2010.08.018
- Bibcode:
- 2010IJHE...3512405Z
- Keywords:
-
- Hydrogen;
- Ammonia borane;
- Alkaline-earth metal hydride;
- Dehydrogenation;
- Borazine