Influence of oxygen vacancies on magnetic and dielectric properties of nanocrystaline barium titanate

Abstract

© 2020 Taylor & Francis Group, LLC. Influence of thermal treatment in H2 atmosphere on magnetic and dielectric properties of nanocrystalline BaTiO3 samples was studied. It was found that increase of the concentration of oxygen vacancies during prolonged annealing in hydrogen leads to a noticeable increase in the diamagnetic response and a decrease in the magnetization and dielectric permittivity. Observed changes of magnetic properties probably are caused by the modification in a state of oxidation of titanium ions in the surface layer. Along with these the experimental results revealed that magnetization of the nanocrystalline BaTiO3 is proportional to the total surface area of nanogranules in the sample.