Effect of Cr substitution by Ni on the cycling stability of Mg2Ni alloy using EXAFS

This figure shows the evolution of local structure in the c direction. As indicated, the crystal lattice underwent a contraction induced by the strong Ni-Cr bond during ball milling. After 5 cycles, the expanded crystal lattice weakened the Ni-Cr bond. The Ni-Cr bond started to form again at the 10th cycle, which made a strong contraction along the [110] direction. After 20 cycles, the strong Ni-Cr bond formed again, which may accompany hydrogen release from this material.185