Dielectric Characteristics in BiFeO 3 -Modified SrTiO 3 Incipient Ferroelectric Ceramics

We investigate the dielectric and ferroelectric properties of Sr1−xBixTi1−xFexO3 solid solutions (x = 0, 0.05, 0.1, 0.15 and 0.2) together with their structures. Through the analysis of Rietveld refinement of powder x-ray diffraction, a cubic structure in space group Pmm is determined for all the compositions. An obvious dielectric relaxation peak differing from SrTiO3 is observed in the present ceramics. The peak temperature Tm increases with increasing x, and it approaches room temperature at x = 0.2. The Vogel—Fulcher law and Curie—Weiss law fittings further confirm the relaxor ferroelectricity in the present ceramics.