LaNi5 related AB5 compounds: Structure, properties and applications

This paper is a comprehensive review of the properties of LaNi5 derivatives and other AB5 compounds with CaCu5 crystal structure (A = Y, lanthanide, Th and B =transition metal, Al, Ge, Si, Sn) and their applications. The crystal structures of the intermetallic compounds are described considering their chemical composition and off-stoichiometry. Same approach is conducted for the metallic hydrides formed by direct reaction of dihydrogen with the intermetallic. The thermodynamic properties of the sorption reaction are presented regarding equilibrium pressure and reversibility. In a second step, outstanding applications are given focusing first on magnetic properties and electrochemical energy storage. Finally, other uses such as gas storage, heat exchange, compression or gas separation and purification are highlighted showing the tremendous possibilities offered by this class of materials.