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ABSTRACT

Oprysk V.O. Synthesis, structure and electrochemical hydrogenation properties of

the АВ 2 and АВ 3 alloys in the{La, Pr, Nd, Y}–(Mg)–{Ni, Co, Mn}systems. – Qualification

research manuscript.

Thesis for the degree of Doctor of Philosophy in the field of knowledge 13 –

Mechanical Engineering, specialty 132 – Materials Science. – Karpenko Physico-

Mechanical Institute of the National Academy of Sciences of Ukraine, Lviv, 2026.

Present work is devoted to the comprehensive investigation of phase formation

patterns, crystal structure, and hydrogen sorption properties of AB 2 and AB 3-type
-
intermetallic compounds and alloys in R–Mg–d-transition metal systems (R = La, Y, Pr,

Nd and/or their mixtures), as well as an assessment of the effectiveness of Ni–Pd and Ni–

Fe nanosized transition metal powders as functional additives to negative electrode

materials of Ni-MH rechargeable batteries.

Chapter 1 provides a systematic analysis of the current state of research on

hydrogen storage methods, including physical and physicochemical approaches, and

reviews the operating principles of Ni-MH electrochemical power sources. Crystal-

chemical features and hydrogen sorption properties of AB 5, AB 2, and AB 3 hydride-forming

compounds and alloys are summarized and discussed. Based on the provided analysis,

the scientific relevance of investigating alloys in R–Mg–d-transition metal system is

substantiated in view of their considerable potential as efficient hydrogen storage

materials for modern energy applications.

Chapter 2 describes the synthesis procedures used for the preparation of samples,

including arc melting, powder sintering, and chemical reduction (for nanosized powders).

A comprehensive set of techniques for investigating the crystal structure and phase

composition of the synthesized materials is presented, including X-ray phase analysis and

X-ray structural analysis with refinement of structural parameters using the Rietveld

method, scanning electron microscopy, and X-ray photoelectron spectroscopy.

Electrochemical properties were assessed by galvanostatic cycling, high-rate discharge

(HRD) measurements, chronoamperometry, cyclic voltammetry, and electrochemical