Zr-substitution in LaNi5-type hydride compound by room temperature ball milling

High-energy ball milling at room temperature has been used to prepare the pseudo-binary compound La1−xZrxNi5 (x=0.5) in amorphous state. The stability of this phase has been investigated by XRD, DSC and DTA. It starts to crystallise into single-phase La0.5Zr0.5Ni5 alloy at 361 °C and undergoes decomposition into LaNi5 and ZrNi5 above 670 °C. Pressure–composition isotherm (PCI) curves of hydrogen absorption have been measured for crystalline La0.5Zr0.5Ni5 alloy and are compared to that of the binary LaNi5 and ZrNi5 compounds.