Structural and Mössbauer spectroscopic study of cubic phase ZrFe2−xMnx hydrogen storage alloy

Cubic (C15) laves phase ZrFe2−xMnx alloys with x = 0.2, 0.4, 0.6, 0.8 have been prepared by arc melting method. The hydrogen storage performance of these alloys is reported here. Hydrogen absorption isotherms have been measured for ZrFe2−xMnx compounds at pressure up to 60 atm and temperature between 303 K and 373 K. The enthalpies of hydride formation, derived from temperature variation of equilibrium pressure for x = 0.2, 0.4, 0.6, 0.8 show the increase of hydride stability with increase of Mn content. 57Fe Mössbauer measurements were carried out on samples and their hydrides formed at 5 bar pressure. 57Fe Mössbauer spectra, measured at room temperature, could be fitted with two sextets and one doublet for all the alloys and their hydrides. This indicates that the sample nature tends to be non-magnetic with the increasing content of Mn.