metallihydride

Metallihydride is a compound formed between a metal or metalloid and hydrogen. In these compounds, hydrogen atoms occupy interstitial sites within the metal lattice structure. The bonding in metallihydrides can range from ionic to covalent, depending on the electronegativity difference between the metal and hydrogen. For instance, Group 1 and Group 2 metals tend to form more ionic hydrides like sodium hydride (NaH), while transition metals often form non-stoichiometric hydrides where the hydrogen content can vary. These materials are often characterized by their ability to absorb and desorb significant amounts of hydrogen, a property that makes them of interest for various applications.

The absorption of hydrogen by metals, leading to metallihydride formation, is often reversible. This process is influenced by factors such as temperature and hydrogen pressure. When heated or when the surrounding hydrogen pressure is reduced, the hydrogen can be released from the metal lattice. This reversible hydrogen storage capability is a key feature driving research into metallihydrides for energy storage solutions, particularly for hydrogen fuel cell technology. Other potential uses include hydrogen purification, heat pumps, and as catalysts in chemical reactions. The specific properties of a metallihydride depend heavily on the constituent metal and the stoichiometry of the compound.