Achieving superior de-/hydrogenation properties of C15 Laves phase Y-Fe-Al alloys by A-side substitution

作者：Li, Ziming; Wang, Hui; Ouyang, Liuzhang; Liu, Jiangwen; Zhu, Min^*

来源：Journal of Alloys and Compounds, 2019, 787: 158-164.

DOI：10.1016/j.jallcom.2019.02.074

• Hydrogen storage alloys
• YFe2
• A-side substitution
• Equilibrium pressure

The strategy of partial substitution was adopted on the A-side of Y-Fe-Al alloys and Y-M-Fe-Al (M = Zr, Ti, V) quaternary alloys with C15 Laves phase were successfully prepared. Reversible hydrogen storage could be realized in these alloys without hydrogen-induced amorphization or disproportionation. The Y-M-Fe-Al alloys showed fast kinetics properties, completing de-/absorption processes within 500s. The Y0.9V0.1Fe1.7Al0.3 alloy could release the maximum amount of hydrogen with 0.79 wt%, which is almost twice as that of YFe1.7Al0.3 alloys. The improvement could be due to the increased desorption equilibrium pressure in Y-M-Fe-Al alloys, which increased from 0.168 to 1.203 atm. Neutron diffraction result indicated that H atoms occupied A2B2 tetrahedral sites in the C15 lattice. Thus, the size of the A2B2 tetra-hedral sites and the hydride formation enthalpy of the substituted alloys were calculated, aiming to figure out a rough relation between them and the desorption equilibrium pressure, while providing some constructive suggestions on composition design in future research.

• 出版日期2019-5-30
• 单位华南理工大学