Dielectric properties of some low-lead or lead-free perovskite-derived materials : Na0.5Bi0.5TiO3-PbZrO3, Na0.5Bi0.5TiO3-BiScO3 and Na0.5Bi0.5TiO3-BiFeO3 ceramics

• Published in: Journal of the European Ceramic Society Vol. 26; no. 14; pp. 3037 - 3041
• Main Authors: MARCHET, P, BOUCHER, E, DORCET, V, MERCURIO, J. P
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier 2006
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Ceramic industries; Chemical industry and chemicals; Electrotechnical and electronic ceramics; Exact sciences and technology; Technical ceramics; Iron oxide; Perovskite type compound; Electrical properties; Bismuth oxide; Dielectric properties; Binary system; Bismuth Iron Oxides Mixed; Perovskites; Experimental study; Lattice parameters; Solid solution; X ray diffraction; Bismuth Titanates; Oxide ceramics; Lead zirconates; Bismuth Sodium Titanates Mixed; Bismuth Scandium Oxides Mixed; Sodium Titanates; Scandium Oxides; Manufacturing; Electroceramics
• ISSN: 0955-2219; 1873-619X
• DOI: 10.1016/j.jeurceramsoc.2006.02.024

Na0.5Bi0.5TiO3 (NBT) and its modifications are known to be new lead-free ferroelectric materials and are promising for environment friendly devices. The systems under investigation were (i) NBT (trigonal/ferroelectric)-PbZrO3 (orthorhombic/antiferroelectric); (ii) NBT (trigonal/ferroelectric)-BiScO3 (trigonal/paraelectric); and (iii) NBT (trigonal/ferroelectric)-BiFeO3 (trigonal /antiferromagnetic). The lattice parameters changed as expected from the respective ionic radii values. For NBT-PZ, the dielectric permittivity showed a large frequency and temperature dispersion suggesting a relaxor-like behaviour dependent on the thermal annealing of the samples. For NBT-BS, the Curie temperature increased with BS content as well as the diffuseness of the phase transition, connected with the introduced disorder. For NBT-BF, the overall behaviour of the permittivity of NBT was maintained up to 50% BF but anomalies of the permittivity appeared close to 600 C, which might have been connected with the onset of magnetic influence for high BF content. 14 refs.