Effect on structure and hydrogen storage characteristics of composite alloys Ti_0.32Cr_0.43V_0.25 with LaNi₅ and rare-earth elements La, Ce, Y

Ti_0.32Cr_0.43V_0.25 and LaNi₅ were prepared independently by arc melting. These two alloys were made into composite as Ti_0.32Cr_0.43V_0.25 + x wt% LaNi₅ (with x = 5, 10 and 20). In addition, an alloy of Ti-Cr-V with rare-earth elements La, Ce and Y were also prepared. These composite alloys were characterized for their structure and hydrogen storage characteristics. Phase analysis and microstructural studies were carried out using powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) techniques. A Rietveld refinement for the alloy 80 wt% Ti_0.32Cr_0.43V_0.25 + 20 wt% LaNi₅ shows five phases assigned as two BCC, La₂O₃, VO₂, and TiCr₂. Hydrogen storage capacity and hydrogen plateau pressure were likely to be affected by the lattice parameter of BCC phase and the formation of secondary phases. The hydrogenation characteristics for these mixed compositions were investigated.