T. Czujko et al. / Journal of Alloys and Compounds 509S (2011) S604–S607
S607
4. Conclusions
The DSC hydrogen desorption peak temperature of the MgH2
constituent in the MgH2 + LiAlH4 composite decreases linearly with
increasing weight fraction of complex hydride component. For the
system magnesium hydride/lithium alanate there is no functional
dependence between energy of activation of MgH2 decomposition
and content of LiAlH4. It was found that lithium alanate thermody-
namically affects process of MgH2 decomposition by formation of
solid solution (aluminum dissolved in magnesium matrix).
The catalytic effects of MgH2 additives on the hydrogen des-
orption properties of the NaBH4 formed after controlled milling of
the (NaBH4 + MgH2) composites have been studied. The DSC des-
orption peak temperature of NaBH4 decreases dramatically with
increasing amount of MgH2 in the composites. This effect is most
likely due to the catalytic effect of Mg which is formed during MgH2
decomposition.
Acknowledgement
This work was partially supported by a grant from the State
Committee for Scientific Research of Poland (N N507 352735)
which is gratefully acknowledged.
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