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method, structural characterization of the synthesized composites and investigation of

hydrogen generation via hydrolysis from the prepared composites.

The third chapter presents the results of experimental studies and their analy-

sis. In particular, the results of mechanochemical hydrogenation of magnesium com-

posites of different quality with catalytic additives are presented. The results of hy-

drogenation of these composites from the gas phase and desorption of hydrogen in

vacuum from synthesized hydride composites at different temperature regimes are
shown. The activation energy was determined for some composites by the method of

thermodesorption spectroscopy. The results of X-ray phase and microstructural stud-
ies of hydride composites and the results of hydrolytic generation of hydrogen from

them using distilled water and chloride solutions of various concentrations are pre-
sented.

In fourth chapter discusses the key findings of the research and provides rec-

ommendations for the optimal composition of synthesized hydride composites with

the best functional parameters for their use in hydrogen hydrolysis devices.

Novel magnesium-based hydride composites with catalytic additives of subox-

ides, complex oxides, and graphite were synthesized for the first time. The catalytic

effect of small amounts of additives on the sorption and desorption properties of Mg

was investigated. It was shown that they significantly improve the sorption kinetics

and reduce the duration of hydrogenation both from the gas phase at different tem-

perature regimes and during mechanochemical synthesis. During desorption in vacu-

um at temperatures up to 350 °C, additives improve the kinetics and reduce the hy-

drogen desorption temperature by 44-74 °C compared to nano-MgH . For some cata-
2
lytic additives, the activation energy was additionally calculated. The synthesized

new hydride composites were tested in reactions of hydrolytic hydrogen generation in

distilled water and MgCl solutions of different concentrations. The mechanisms of
2
the hydrolysis reaction in pure water and magnesium chloride solutions were estab-

lished and substantiated.

The obtained results can be used as reference material for analyzing the hydro-

gen sorption capacity, hydrogenation duration, sorption/desorption temperatures, and

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