A new material for hydrogen storage; ScAl{sub 0.8}Mg{sub 0.2}

A novel aluminium rich alloy for hydrogen storage has been discovered, ScAl{sub 0.8}Mg{sub 0.2}, which has very promising properties regarding hydrogen storage capacity, kinetics and stability towards air oxidation in comparison to hydrogen absorption in state-of-the-art intermetallic compounds. The absorption of hydrogen was found to be very fast, even without adding any catalyst, and reversible. The discovered alloy crystallizes in a CsCl-type structure, but decomposes to ScH{sub 2} and Al(Mg) during hydrogen absorption. Detailed analysis of the hydrogen absorption in ScAl{sub 0.8}Mg{sub 0.2} has been performed using in situ synchrotron radiation powder X-ray diffraction, neutron powder diffraction and quantum mechanical calculations. The results from theory and experiments are in good agreement with each other. - Graphical abstract: Hydrogen absorption in ScAl{sub 0.8}Mg{sub 0.2} studied by in situ synchrotron radiation powder X-ray diffraction. The hydrogen absorption properties were studied by neutron diffraction and quantum mechanical calculations.