The ferroelectric transition temperature as an intrinsic probe for sintered nanocrystalline BaTiO3 synthesized under supercritical conditions
Résumé
We have investigated the sintering behaviour of cubic BaTiO3 nanoparticles obtained under supercritical conditions. The ferroelectric properties of samples sintered between 950 and 1300 °C were measured from room temperature up to 200 °C and in the frequency range 100 Hz–10 kHz. The influence of the initial powder characteristics on the microstructure and dielectric properties of ceramics have been investigated. The ferroelectric transition temperature was used as an intrinsic probe for the ceramic characterization and was then found to be dependent on the Ba:Ti ratio of the initial powder. Understanding the role of the key parameters at different scales (bulk and nanoscale composition, tetragonal distortion, microstructure) on the permittivity, losses and transition temperature would lead to a possible modulation of ferroelectric properties.