Crystal Structure, Raman Spectroscopy, and Ab Initio Calculations of a New Bialkali Alanate K2LiAlH6

Alanates, a Comprehensive Review

Hydrogen storage is widely recognized as one of the biggest not solved problem within hydrogen technologies. The slow development of the materials and systems for hydrogen storage has resulted in a slow spread of hydrogen applications. There are many families of materials that can store hydrogen; among them, the alanate family can be of interest. Basic research papers and reviews have been focused on alanates of group 1 and 2. However, there are many alanates of transition metals, main group, and lanthanides that deserve attention in a review. This work is a comprehensive compilation of all known alanates. The approaches towards tuning the kinetics and thermodynamics of alanates are also covered in this review. These approaches are the formation of reactive composites, double cation alanates, or anion substitution. The crystallographic and X-ray diffraction characteristics of each alanate are presented along with this review. In the final sections, a discussion of the infrared, Raman, and thermodynamics was included.

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

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.

Crystal feature and electronic structure of novel mixed alanate LiCa(AlH4)3: a density functional theory investigation

The H coordinates are predicted for LiCa(AlH₄)₃ in which Li–H bonding and Ca–H anti-bonding interactions are illustrated.

Structures of aluminium-based light weight hydrides

Light weight hydrides based on aluminium are among the most promising materials for hydrogen storage applications since the hydrogen content is up to 11 wt%. The crystal structures of many promising aluminium-based compounds have been determined and refined during the last years. This review gives an overview of structures of tetra-alanates (with AlH4 tetrahedra), hexa-alanates (with AlH6 octahedra) and different modifications of AlH3. The structure determinations are based on powder diffraction with X-rays, synchrotron X-rays and neutrons. In most structural work neutron diffraction has been used in order to determine accurate hydrogen/deuterium positions. In addition, density functional theory has been used both to predict new structures among these compounds and in combination with experimental work.