Magnesium effect on hydrogen-induced amorphization of Sm2-xMgxNi4 compounds

摘要

The magnesium effect on hydrogen-induced amorphization (HIA) of Sm2-xMgxNi4 compounds is investigated in this work. It is found that the HIA phenomenon occurs in the compounds with x = 0, 0.25 and 0.5. The amorphous hydrides do not desorb hydrogen at 298 K. However, the pseudo-binary Sm1.25Mg0.75Ni4 compound can reversibly absorb and desorb hydrogen without the occurrence of HIA during hydrogen absorption and desorption cycles at 298 K. Hence, it is suggested that the critical R-A/R-B ratio for HIA of pseudo-binary AB(2) compounds should shift to a slightly higher value than the empirical value 137 for the occurrence of HIA in binary AB(2) compounds. (C) 2017 Elsevier B.V. All rights reserved.