Hydrogenation behaviour of Ce-based AB5 intermetallic compounds

In the present work, the effect of Zr on the hydrogenation behaviour of CeNi5 intermetallic compound has been studied. All intermetallic compounds have been synthesized by arc melting method in the argon atmosphere and well characterized by the means of XRD and SEM. The elemental composition of each sample has also been investigated using EDX technique. EDX spectrum confirms the elements present in the sample and the exact quantitative composition of these elements. The lattice constant and volume was found to increase with Zr substitution. Pressure composition isotherm has been carried out for CeNi5-xZrx (x = 1, 2) alloys in the temperature and pressure ranges of 293 <= T <= 333 K and 0.5 <= P <= 35 bar, respectively. The plateau pressure was found to reduce significantly, which makes these alloys more useful for practical applications in comparison to parent alloy (CeNi5). The enthalpy and entropy for the systems has been calculated using Van't Hoff plot. (c) 2006 Elsevier B.V. All rights reserved.