Yavorskyi Y. Effect of mechanical activation on electronic structure of mixtures of Si, Al, Ti, Fe nanooxides and charge capacity of lithium current supplies with cathodes on these mixtures basis.

Thesis for the candidate degree in physics and mathematics according to the speciality 01.04.07 - solid state physics. - Frantsevich Institute for the Problem of Materials Science of NASU, Kyiv, 2016. Effect of mechanical activation of TiO2+SiO2, g-Fe2O3+SiO2, a-Fe2O3+SiO2, Al2O3+a-Fe2O3 mixtures on the morphological, atomic- and electronic-structural characteristics of these mixtures has been studied by means of scanning and transmission electron microscopy, X-ray diffraction and emission spectroscopy. Dependence of charge capacity of lithium current supplies with cathodes on these mixtures basis on changes of the above-mentioned characteristics has been investigated applying the galvanostatic cycling method. The energy redistribution of the valence electrons of nanocomposites components as a result of the origin of interatomic interaction between surface atoms of nanoparticles due to mechanical activation of mixtures has been revealed. It has been found that interatomic interaction between surface nanoparticles was a result of increasing occupation of the Op-states due to the overlapping of the Оp-orbitals. At the same time occupation of the Opп-binding states has been followed by increasing charge capacity of lithium current supplies with cathodes on these mixtures basis and cycling whereas occupation of nonbinding high-energy Op-states resulted in increasing of charge capacity and recombinational ability of lithium ions and formation of LiO oxide (passivation) film on the surface of cathode material of lithium current supplies. These results can be used in enterprises engaged in manufacturing mobile power sources, as well as in scientific research laboratories that develop new cathode material of lithium ion power sources and high sorption materials.