Mechanochemical synthesis and thermal decomposition of Mg(AlH4)2

Abstract: Magnesium alanate Mg(AlH4)2 has been synthesized by mechanochemically activated metathesis reaction between NaAlH4 and MgCl2 without solvent, this metathesis reaction proceeded completely. The thermal decomposition behavior of solvent-free Mg(AlH4)2 has been analyzed by TG/MS and DSC. It has been confirmed that Mg(AlH4)2 decomposes in two steps: the first decomposition reaction Mg(AlH4)2 →MgH2 +2Al+3H2 is exothermic and starts at about 115°C. The second one is endothermic in total and starts at about 240°C, although the formation reaction of Al3Mg2 (3Al+2Mg→Al3Mg2) is exothermic. [Copyright &y& Elsevier]