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Bimetallic Ni-Cu nanoparticles with different (Ni/Cu) ratio have been synthesized via fast and simple one-pot reducing Ni(OH)2/Cu(OH)2 pulp by hydrazine in water/ethylene glycol solutions. Using scanning electron microscopy (SEM), it was found that all obtained nanopowders are polydisperse with the particles sizes within 20–70 nm and the mean diameter of particles slightly depends on the Ni/Cu ratio. Using XRD phase-structural analysis, it was found that with increasing Cu amount in the initial mixture from 20 to 50%, the lattice parameter for Ni phase increases from 3.527 to 3.560 A but the lattice parameter of Cu changes more slightly (3.594 … 3.606 A). Besides, using precision EDX technique, it was found that obtained nanoparticles may be considered as a core–shell type in which a core consists of copper but a shell consists of a nickel-copper solution. Hydrogenation properties of obtained Ni-Cu nanoparticles have been studied, and it has been shown that the initial capacity of Ni-Cu-NPs depends on the specific surface area and compositions of the samples.

Magnesium hydride (MgH2) is a hydrogen-rich compound generating significant amounts of hydrogen in the process of hydrolysis, i.e., in the course of its chemical interaction with water or with aqueous solutions. This process is of great interest for the on-site hydrogen generation aimed at application of H2 as a fuel for PEM fuel cells. We propose a review of recent reference publications in the field and also present the results of our own research. The increase of the rates of H2 release and the completeness of transformation of MgH2 are two important goals, which can be attained by optimizing the size of the powders of MgH2 by ball milling, by using catalysts added to MgH2 and to aqueous solutions, and by increasing the interaction temperature. The effect of these parameters on the degree of conversion and the rates of hydrogen evolution are analyzed in detail and the best systems to reach the efficient hydrolysis performance are identified. The mechanism of catalytic hydrolysis is proposed, while further improvements of the process of hydrolysis are required and additional studies of this important topic are needed.

Amorphous MgNi and MgNi0.5Co0.5 composites were prepared by mechanical ball grinding in an argon atmosphere. The electrodes made of these composites are characterized by high electrochemical discharge capacity: 872 mA · h/g for MgNi and 309 mA · h/g for MgNi0.5Co0.5. The cyclic stability (S30) of the MgNi0.5Co0.5 electrode (42%) is somewhat higher compared to MgNi (26%). Reduction in the capacity of electrodes is associated with bulk and corrosion processes. The MgNi0.5Co0.5 electrode increases its capacity to a greater extent than MgNi after deep discharge.

The LaMgNi4–xCox (x = 0, 0.33, 0.67, 1) alloys are prepared by sintering and prolonged heat treatment at 500°C, with the main cubic phase of MgCu4Sn type. The alloy samples ball-milled in an argon atmosphere show the glass-forming ability. Electrochemical experiments of the LaMgNi4–xCox electrodes are performed at charge and discharge current densities of 100 mAh. The maximum discharge capacity is exhibited by the powdered alloys (218–302 mAh/g) compared to the ball-milled ones (92–134 mAh/g). The cobalt content of the LaMgNi4–xCox alloys influences the electrode characteristics. The highest discharge capacity is shown by the powdered alloy with x = 0.33. The ball-milled alloys have slightly higher cyclic stability.

The advantages of reactive ball grinding for preparation of new efficient Mg-based hydrogen storage materials are discussed. Magnesium-based nanocomposites were synthesized with additions of η-Zr4Fe2O0.5 intermetallic compound, which is characterized by enhanced resistance to disproportionation in hydrogen and can prolong the cyclic life of materials. The improvement of hydrogen absorption parameters for Mg–intermetallic composites was observed. It was shown that fourfold increase in the reaction rate during mechanochemical synthesis of MgH2 and decrease in hydrogen desorption temperature by 80°C were induced by catalytic additions.