Magnesium- and intermetallic alloys-based hydrides for energy storage: modelling, synthesis and properties

Abstract

Hydrides based on magnesium and intermetallic compounds provide a viable solution to the challenge of energy storage from renewable sources, thanks to their ability to absorb and desorb hydrogen in a reversible way with a proper tuning of pressure and temperature conditions. Therefore, they are expected to play an important role in the clean energy transition and in the deployment of hydrogen as an efficient energy vector. This review, by experts of Task 40 ‘Energy Storage and Conversion based on Hydrogen’ of the Hydrogen Technology Collaboration Programme of the International Energy Agency, reports on the latest activities of the working group ‘Magnesium- and Intermetallic alloys-based Hydrides for Energy Storage’. The following topics are covered by the review: multiscale modelling of hydrides and hydrogen sorption mechanisms; synthesis and processing techniques; catalysts for hydrogen sorption in Mg; Mg-based nanostructures and new compounds; hydrides based on intermetallic TiFe alloys, high entropy alloys, Laves phases, and Pd-containing alloys. Finally, an outlook is presented on current worldwide investments and future research directions for hydrogen-based energy storage.

Severe Plastic Deformation through High-Pressure Torsion for Preparation of Hydrogen Storage Materials -A Review

“…Mg-based alloys have a large hydrogen storage capacity (up to 7.6 wt.% in MgH 2 ) and good absorption/desorption reversibility, and they are becoming more and more important as solid hydrogen storage materials. 88) Nevertheless, most Mg-based alloys suffer from sluggish kinetics and high dehydrogenation temperatures due to the high activation energy E a = 143.0160.6 kJ/mol 89) and decomposition enthalpy of MgH 2 (75 kJ mol ¹1 H 2 ). 90) The HPT process is a good method to introduce SPD in different Mg-based hydrogen storage materials.…”

Producing Alkali Metal Hydrides from Hydroxides

“…This review focuses on the production of alkali metal hydrides. Metal hydrides are capable of storing hydrogen at high volumetric densities and may be safer than mechanical methods of hydrogen storage due to their operation at typically low temperatures and pressures. − There are various types of metal hydrides including intermetallic compounds (AB 5 , AB, AB 2 , A 2 B, AB 3 , solid solution) and complex hydrides (alanates, borohydrides, amides). ,− …”

Towards Pareto optimal high entropy hydrides via data-driven materials discovery

“…2,3 In terms of hydrogen storage, intermetallic compounds and their substituted alloys have long been studied as promising candidates because they achieve hydrogen volumetric densities on par with or exceeding compressed gas (e.g., 700 bar H 2 ) at signicantly lower pressures. [4][5][6][7][8][9][10][11] While lighter weight complex hydrides have been intensively investigated in the context of light duty vehicle applications, 12,13 high performance but heavier metal alloybased hydrides could be attractive in stationary applications where weight of the hydride bed is of less concern, i.e. stationary and seasonal grid storage and hydrogen compression.…”

“…, 700 bar H 2 ) at significantly lower pressures. 4–11 While lighter weight complex hydrides have been intensively investigated in the context of light duty vehicle applications, 12,13 high performance but heavier metal alloy-based hydrides could be attractive in stationary applications where weight of the hydride bed is of less concern, i.e. stationary and seasonal grid storage and hydrogen compression.…”