Electrochemical hydrogenation properties of Nd₂MgT₉ (T = 3d-metals) multi-phase alloys

Chem. Met. Alloys 15 (2022) 26-33

https://doi.org/10.30970/cma15.0426

Yuriy VERBOVYTSKYY, Volodymyr OPRYSK, Yuriy DUBOV, Ihor ZAVALIY

A series of alloys based on the intermetallic compounds Nd₂MgNi₉ and Nd₂MgCo₉ with the compositions Nd₂MgT₈T’ (T = Ni, Co, T’ = Fe, Co, Ni, Cu) and Nd₂MgNi_9-xCo_x (x = 0, 3, 4.5, 6, 9) were synthesized and their electrochemical hydrogenation properties studied. The alloys contained three phases: pseudo-binary AB₂ Laves (SnMgCu₄ structure type), AB₃ (PuNi₃ structure type), and AB₅ (CaCu₅ structure type) phases. Electrochemical characteristics such as discharge capacity and capacity retention were studied. The highest capacity (297 mA h/g) was achieved by the Nd₂MgNi_9-xCo_x (x = 6) alloy and may be related to the chemical and multi-phase composition.

Discharge capacity vs cycle number for Nd₂MgNi_9-xCo_x (x = 0, 3, 4.5, 6, 9), current density 50 mA/g.

Keywords

X-ray powder diffraction / AB₃ alloys / Transition metals / Electrochemical hydrogenation