Investigation of the Hydrogen Storage Performance of the LaNi₅ Alloy

The hydrogen storage performance of LaNi₅ was systematically investigated under different pressure conditions. Hydrogen absorption experiments using LaNi₅ were conducted at hydrogen pressures of 10, 20, and 30 bar. Structural and morphological characterizations were carried out using Raman spectroscopy, XRD, SEM, and BET surface area analyses. Raman results indicated that the main LaNi₅ phase was preserved after hydrogen absorption, while the formation of La₂O₃ on the surface increased. The crystallite size of pristine LaNi₅ and hydrogen-absorbed LaNi₅ was found to increase from 8.9 nm to 10.10 nm after hydrogenation. SEM and BET analyses revealed that LaNi₅ exhibits a heterogeneous grain morphology with a specific surface area of 2.77 m²/g. The hydrogen storage capacity was measured as 0.8 wt% at 10 bar, 1.2 wt% at 20 bar, and 1.4 wt% at 30 bar. The obtained results demonstrate that increasing pressure accelerates hydrogen diffusion into the metal lattice and promotes hydride phase formation. The study confirms the safe and reversible hydrogen storage potential of LaNi₅ under near-room-temperature conditions and provides important insights for performance optimization in pressure-controlled systems.