Diffuse Ferroelectric Phase Transition and Relaxor Behaviors in Ba-Based Bismuth Layer-Structured Compounds and La-Substituted SrBi4Ti4O15
Abstract:The dielectric characteristics of BaBi2Nb2O9, BaBi4Ti4O15, BaBi8Ti7O27, and La-substituted SrBi4Ti4O4 were investigated to discuss their ferroelectric phase transition and relaxor behaviors. BaBi2Nb2O9 showed typical relaxor behaviors, and a shift of Tm with increasing frequency was observed in BaBi4Ti4O15 and SrBi4−xLaxTi4O15 (x=0.8, 1.0) but they underwent a real paraelectric–ferroelectric phase transition on zero-field cooling, while BaBi8Ti7O27 showed a normal ferroelectric nature. The reduced concentration and weakened coupling of the dipoles related to A-site bismuth are believed to be responsible for the appearance of short-range electric ordering and the relaxor behaviors in these bismuth layer-structured compounds.
Document Type: Research Article
Affiliations: Department of Materials Science & Engineering, Zhejiang University, Hangzhou 310027, China
Publication date: September 1, 2006