Dielectric and ferroelectric properties of xBaZr_0.52Ti_0.48O₃–(1−x)BiFeO₃ solid solution ceramics

Abstract

xBaZr_0.52Ti_0.48O₃–(1−x)BiFeO₃ (short for xBZT–(1−x)BFO) solid solution ceramics were synthesized by conventional solid state reaction method. The microstructure, dielectric and ferroelectric properties of xBZT–(1−x)BFO (x = 0.2–0.5) solid solution ceramics have been investigated systematically. The XRD results show that the crystal structure of xBZT–(1−x)BFO solid solution ceramics evolves gradually from rhombohedral to tetragonal phase and the lattice parameters increase as BZT content increases. The grain size of xBZT–(1−x)BFO ceramics increases initially to the maximum (x = 0.3) and then decreases with the increase of BZT content. As BZT content increases, the temperature at which the maximum in the dielectric constant appears and the corresponding maximum dielectric constant increase first and then decrease. There is obvious frequency dispersion and diffuse phase transition in xBZT–(1−x)BFO solid solution ceramics, and the dielectric diffuseness is enhanced by a certain amount of BZT. As BZT content increases, the leakage current density of xBZT–(1−x)BFO ceramics increases first and then decreases, while the remnant polarization and coercive field decrease initially by a large margin and then increase. Moreover, the remnant polarization and coercive field decrease as frequency increases.