Structural and dielectric relaxor properties of Ba_1-xMg_xTiO₃ ceramics prepared through a hydrothermal route

ABSTRACT

Polycrystalline samples of lead-free Ba_1-xMg_xTiO₃ (where x = 0.05, 0.10, 0.15) have been fabricated by a hydrothermal method. Single-phase perovskite-type X-ray diffraction patterns were observed and samples have a phase with a tetragonal structure at room temperature for all compositions. The SEM image of the powder shows the agglomeration with increment of Mg concentrations. Small grains with average grain sizes of ∼20 ± 5 nm are uniformly distributed over the mesocrystals. TEM specimens show well-dispersed spherical barium magnesium titanate nanoparticles and diameter of these particles is around 270–300 nm. A dielectric study of Ba_1-xMg_xTiO₃ ceramics as a function of temperature suggested that with increasing substitution concentration the dielectric constant decreased and the Curie temperature shifted towards the lower temperature side. The dielectric diffusivity (γ) was found to be maximum (1.86) for substitution of x = 0.10 in Ba_1-xMg_xTiO₃ compounds. The activation energy (Ea) was found to increases with increasing substitution concentration in BMT compounds.

KEYWORDS:

• BMT
• ferroelectric
• X-ray diffraction
• SEM
• TEM
• dielectric constant

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Authors are grateful to the Defence Research and Development Organization (DRDO), Govt. of India, for financial support under the research project [ERIP/ER/1303129/M/01/1564].