Quantitative description of the phase transition of Aurivillius oxides Sm modified BaBi4Ti4O15 ceramics

BaBi4Ti4O15 + xwt.%Sm2O3 (x = 0.00, 0.25, 0.50, 0.75) ceramics were prepared by the solid-state reaction method. The effect of samarium additives on the structural and electrical properties of BBT ceramic was investigated. XRD patterns indicate that all ceramics are an m=4 members of Aurivillius oxides and no secondary phases were detected. A broad dielectric peak in frequency dependent dielectric spectrum is observed during the phase transition of all the BBT ceramics. The modified Curie-Weiss law, Vogel-Fucher relationship and Lorentz-type law were used to describe the phase transition behavior. The relaxor behavior was described well by the modified Curie-Weiss law and Vogel-Fucher relation. The effect of samarium additives on the degree of relaxation and diffuseness of BBT ceramics was discussed. (C) 2015 Elsevier B.V. All rights reserved.