Relaxor or classical ferroelectric behavior in A site substituted perovskite type Ba1-x (Sm0.5Na0.5)x TiO3

• Published in: Physica status solidi. A, Applications and materials science Applications and materials science, 2006-04, Vol.203 (5), p.987-996
• Main Authors: Abdelmoula, N., Chaabane, H., Khemakhem, H., Von der Mühll, R., Simon, A.
• Format: Article
• Language: English
• Subjects: 77.22.Ch; 77.22.Gm; 77.80.Bh; 77.84.Dy
• ISSN: 1862-6300; 0031-8965; 1862-6319
• DOI: 10.1002/pssa.200521465

New ferroelectric ceramics of ABO3 perovskite type were synthesized in the Ba1–x (Sm0.5Na0.5)x TiO3 system by solid state reaction technique. The effect of the replacement of barium by samarium and sodium in the A cationic site on structural and physical properties was investigated. These compounds crystallize with tetragonal or cubic symmetry. The material is classical ferroelectric for 0 ≤ x ≤ 0.1 and 0.5 ≤ x ≤ 0.6, and present a relaxor behavior for 0.2 ≤ x ≤ 0.4. The dielectric behavior depends upon the cationic disorder in the A site and the cell size. Small rate substitution allows a ferroelectric‐paraelectric transition. For higher rate of substitution the possible random position of the Sm–Na cations brings to a relaxor sate and when the substitution rate x becomes higher than 0.5, the material comes back to a ferroelectric state due to the reduced cell size. Some of these new compositions are of interest for applications due to their physical properties and environmentally friendly character. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)