Structure and dielectric properties of Sm3+ modified Bi4Ti3O12- SrBi4Ti4O15 intergrowth ferroelectrics
Year: 2020
Type: article
Abstract: Novel samarium modified intergrowth ferroelectric ceramics, namely Bi4Ti3O12-SrBi4Ti4O15, were synthesized by conventional solid state reaction method and sintered at 1100°C for 5 h. X-ray diffraction studies revealed the formation of a single phase with the signature of intergrowth oxide and plate like morphology was observed by scanning electron microscopic analyses. The orthorhombicity, the grain size and transition temperature were found to decrease with the increase of Sm content. The dielectric and modulus measurements were performed at different temperatures and frequency ranges. The transition temperature was found to be around 500 °C. The variations of imaginary part of modulus and dielectric constant with the temperature showed diffuse phase transition. The results are corroborated to the defect based mechanism and Curie deviation factor was evaluated by using the modified Curie-Weiss law. Polarization-electric filed curves displayed a typical narrow hysteresis loop at room temperature by applying an electric field of 70 kV/cm. However, above room temperature the hysteresis loop area was found to be increased. The overall results revealed that the complex dipoles and oxygen vacancies are playing a dominant role in the dielectric and electrical properties, and therefore the adopted intergrowth processing was found to be an effective approach to obtain potentially good ferroelectric materials.
DOI: 10.2298/pac2003260s
Institution: Osmania University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W3082437124