Hydrogen storage intermetallic compounds

The intermetallic compound LaNi is well-known as a suitable material for hydrogen storage. Pseudobinary compounds with the same CaCu -type structure can be easily formed by partial substitution of nickel. Depending upon the rate and the nature of substitution, the hydriding properties (stability, maximum H-content, interstitial sites occupied by hydrogen. ..) are modified (1). 

L Schlapbach, Ed. Hydrogen. In Intermetallic Compounds I and II, Vols 63 and 67 of Topics in Applied Physics. Berlin Springer Verlag, 1988. G G Libowitz. Proceedings of the Symposium, Hydrogen Storage Materials, Batteries and Electrochemistry. The Electrochemical Society, Proceedings 92 5 3, 1992. 

Intermetallic compounds of zirconium with kon, cobalt, and manganese absorb and desorb considerable amounts of hydrogen, up to ZrMri2 [68417-38-9] (128) and ZrV2H 2 [63440-37-9] (129). These and other zirconium intermetallic compounds are being extensively studied for possible hydrogen storage appHcations (130). 

Guenee and Yvon [217] synthesized LaNi MOj intermetallic with a YNi Alj-type crystal structure. However, its hydrogen storage properties are no better than those of LaNij-type because it could barely absorb -1.4 wt.%Hj forming LaNi MnjH and its equilibrium temperature at 1 bar H, is about 60°C. No attempt of nanostructuring the compound by ball milling was made. 

Table 7.2. Intermetallic compounds useful in hydrogen storage...

Table 1.3 Hydrogen storage properties of intermetallic compounds (from [12])...

This could have far-reaching consequences, as mechanically induced disorder can be a factor in activation of well-ordered intermetallic compounds (alloys) for reversible reactions with molecular hydrogen. Figure 1.20b shows the PCT plots, which details hydrogen sorption properties for B2-type FeTi, an important hydrogen storage alloy with capability for reversible storage at room temperature applications. The plateau of equilibrium sorption is lowered in ball milled, disordered FeTi in comparison with the not-milled counterpart. Therefore, the alloy has been... 

Tarasov, B.P., and Shilkin, S.P. (1995) About an opportunity of isolation and storage of high-purity hydrogen of with the help of hydride-forming intermetallic compounds. Zh. Prikl. Khim., 68, No. 1, 21-26 (in Russian). 

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