Solid State Hydrogen Storage in Alanates and Alanate-Based Compounds: A Review

Abstract

The safest way to store hydrogen is in solid form, physically entrapped in molecular form in highly porous materials, or chemically bound in atomic form in hydrides. Among the different families of these compounds, alkaline and alkaline earth metals alumino-hydrides (alanates) have been regarded as promising storing media and have been extensively studied since 1997, when Bogdanovic and Schwickardi reported that Ti-doped sodium alanate could be reversibly dehydrogenated under moderate conditions. In this review, the preparative methods; the crystal structure; the physico-chemical and hydrogen absorption-desorption properties of the alanates of Li, Na, K, Ca, Mg, Y, Eu, and Sr; and of some of the most interesting multi-cation alanates will be summarized and discussed. The most promising alanate-based reactive hydride composite (RHC) systems developed in the last few years will also be described and commented on concerning their hydrogen absorption and desorption performance.

Metals in Hydrogen Technology

“…In recent decades, complex metal hydrides such as borohydrides, alanates, and amides have been intensively investigated as potential material for hydrogen storage applications [2][3][4][5].…”

“…This finding led to the renewed interest of the scientific community in complex metal hydrides as potential hydrogen storage media. Milanese et al [3], in their work, report on the preparative methods; the crystal structure; the physico-chemical and hydrogen absorption-desorption properties of the alanates of Li, Na, K, Ca, Mg, Y, Eu, and Sr. In addition, they describe some of the most interesting multication alanates.…”

Lightweight hydrides nanocomposites for hydrogen storage: Challenges, progress and prospects

“…Storing hydrogen in solid-state materials is a promising way to meet the requirements for on-board applications [4,5]. The hydrogen gas can be absorbed in solid-state materials in molecule form (physisorption) or atom form (chemisorption) [6].…”

A new mutually destabilized reactive hydride system: LiBH4–Mg2NiH4

“…In the last decades, the hydrogen absorption and desorption properties of complex metal hydrides such as borohydrides [1,2] , amides [3] and alanates [4] have been extensively investigated, due to their high gravimetric hydrogen storage capacity [5,6] . However, the reaction enthalpies of the complex metal hydrides are usually too high for most applications.…”