Phase Transitions and Dielectric Properties of Modified BSPT Ceramics

• Published in: Ferroelectrics Vol. 479; no. 1; pp. 35 - 42
• Main Authors: Politova, E. D., Golubko, N. V., Kaleva, G. M., Mosunov, A. V., Stefanovich, S. Yu, Segalla, A. H.
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis 26.04.2015; Taylor & Francis Ltd
• Subjects: Additives; BiScO; ceramic solid solutions; Ceramics; Curie temperature; Dielectric properties; Ferroelectric materials; ferroelectric phase transitions; Ferroelectrics; KCl additives; Melting; morphotropic phase boundary; NaCl/KCl and CaCl; PbTiO; Perovskite; Phase boundaries; Phase transitions; Solid solutions
• ISSN: 0015-0193; 1563-5112
• DOI: 10.1080/00150193.2015.1011581

Influence of complex NaCl/KCl and CaCl 2 /KCl additives (with molar ratios 1:1 and 0.75:0.25, respectively) with low melting temperatures on structure, dielectric and polar properties of ceramic solid solutions on the base of the composition from Morphotropic Phase Boundary in the system (1-x)BiScO 3 - xPbTiO 3 with x = 0.645 (BSPT) was studied. Using the initial BSPT powders prepared from nitrates solutions dense single phase ceramic samples doped by the additives in amounts 5-15 w.% were obtained at 1050°C (2 h). The shift of initial BSPT composition from mixture of rhombohedral and tetragonal phases to tetragonal in case of the NaCl/KCl additives and to pseudocubic (rhombohedral) in case of the CaCl 2 /KCl additives was observed. Slight increase in the Curie temperature T C value from 673 to 681-679 K initiated by the addition of K + ions into A site of perovskite lattice was observed in the samples doped by the NaCl/KCl additives, while monotonous decrease of the T C value was typical of the compositions doped by the CaCl 2 /KCl additives.