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this method of obtaining hydrogen can be used to power fuel cells (FC). However,

the result of the interaction of magnesium hydride with water is magnesium hydrox-

ide (Mg(OH) ), which is slightly soluble (0,0012 g/100 ml). During MgH hydrolysis,
2
2
a layer of Mg(OH) rapidly forms on the hydride particle surface, stopping the reac-
2
tion. To overcome this obstacle, various solutions of acids or salts are used, for ex-

ample, magnesium chloride (MgCl ).
2

This dissertation work focuses on addressing the crucial challenge of enhanc-
ing the kinetics of hydrogen sorption-desorption reactions in magnesium. To achieve

this objective, novel composite materials based on magnesium hydride with catalytic
additives were synthesized using a mechanochemical method. The kinetics of their

gas-phase sorption, desorption, and hydrogen generation via hydrolysis reactions
were thoroughly investigated. The effect of catalysts (ІМС, suboxides of ІМС, com-

plex oxides) as well as graphite on the formation and properties of magnesium hy-

dride composites during mechanical milling was elucidated. The hydrolysis-based

production of hydrogen from these composites in aqueous solutions of MgCl of var-
2
ying compositions was also studied.

In the first chapter provides a comprehensive overview of the existing litera-

ture related to the synthesis and properties of magnesium hydride-based composite

materials for hydrogen storage applications. The focus is on the impact of various

catalytic additives on the hydrogen sorption-desorption kinetics, morphology, micro-

structure, activation energy of desorption, and cyclic stability of these materials. Ad-

ditionally, the chapter delves into the details of hydrogen generation via hydrolysis

from magnesium hydride and its composites, highlighting the influence of different

factors such as reaction medium composition, magnesium hydride synthesis parame-

ters, and hydrolysis conditions. Furthermore, the intrinsic hydrogen sorption proper-

ties of the catalytic additives employed in this study are discussed.

Second chapter outlines the experimental procedures and equipment employed

in the study of magnesium hydride-based composite materials for hydrogen storage

applications. It provides detailed descriptions of the methods utilized for: hydriding

of magnesium and its composites from the gas phase and via a mechanochemical

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