Dielectric and multiferroic properties of two-layered SrBi2Nb2-xFexO9 Aurivillius compounds

Abstract Aurivillius phase SrBi 2 Nb 2- x Fe x O 9 ( x  = 0, 0.1, 0.2, 0.3, 0.4 and 1) ceramics prepared by conventional solid-state method. The introduction of Fe does not change the layered perovskite structure of SrBi 2 Nb 2 O 9 . Upon increasing Fe content, the T m of the samples shifts from 437 °C ( x  = 0) to 524 °C ( x  = 0.4) due to lattice effect. Temperature dependence of dielectric permittivity described according to modified Curie-Weiss law. When reaching up x  = 0.4, the diffuseness of the dielectric peak becomes more pronounced. The minimum value of P r and E c obtained when x  = 0.3 because of Fe 3+ weakens Nb-O hybridization and more oxygen vacancies appeared in samples. The antiferromagnetic properties arise for the samples is explained by super exchange interaction (Fe 3+ -O-Fe 3+ ).