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nanostructured powders based on transition d-metals are outlined. Characterization

techniques such as X-ray powder diffraction and scanning electron microscopy are

described. Particular attention is given to the methods for evaluating electrochemical

properties, including electrode preparation, voltammetric, galvanostatic, and

chronoamperometric measurements. Gas-phase hydrogenation procedures for alloys

and hydrolytic testing of powders as catalysts are also detailed.

The third chapter presents the results of a comprehensive study of the

structural, morphological and electrochemical properties of nanostructured materials

synthesized by various methods. For the first time, the phase composition,

microstructure and electrochemical characteristics of Raney type powders in the Ni–

Co–Fe and Ni–Co–Pd systems synthesized by leaching were determined. SEM and

XRD analyses confirmed their nanocrystalline structure and revealed specific

geometric features of particle morphology. The highest discharge capacities were

observed for Co Fe and Co Fe powders. A decrease in iron content in the Ni–
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Co–Fe system improved corrosion resistance and electrochemical charge-discharge
parameters. The phenomenon of hydrogenation of nanostructured materials based on

Ni, Co, Fe from the gas phase under normal conditions has been established for the

first time. It has been shown that nanostructured Ni-Co-Fe powders, obtained by the

leaching and reduction methods, absorbed up to 0.9 H/f.o at 0.2…1 MPa H pressure.
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Chemically reduced binary Ni–Co powders showed that the particle formation

kinetics depend on the Ni/Co ratio. The Ni Co composition demonstrated the
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highest electrochemical discharge capacity (62.6 mА·h/g), which demonstrated lower

high-rate performance compared to Ni.
Nanostructured Ni, NiCo, and Co powders obtained by laser ablation in water

and air were also studied. It was found that synthesis conditions significantly affect

oxidation state, particle size and phase composition. For Ni and NiCo, hydrogen

insertion into the metal matrix was the dominant mechanism, while Co-based

materials exhibited redox-type behavior. The applicability of such powders as anode

materials and as conductive additives for negative electrodes in Ni-MH batteries was

demonstrated.
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