Re-entrant type relaxor behavior in (1-x) BaTiO3 -xBiScO 3 solid solution

Abstract

The solid solution of (1-x) BaTi O3 -xBiSc O3 was synthesized by solid state reaction and its dielectric properties were studied by impedance spectroscopy. A dielectric anomaly was found in the temperature ranges of -30-13 °C and -60-20 °C for 0.95BaTi O3 -0.05BiSc O3 and 0.90BaTi O3 -0.10BiSc O3, respectively. The frequency dependence of the anomaly exhibits dielectric relaxation satisfying the Vogel-Fulcher law, indicating relaxorlike behavior. The relaxor state in the (1-x) BaTi O3 -xBiSc O3 solid solution occurs after the ferroelectric phase transition upon cooling, indicating a re-entering phenomenon. Piezoresponse force microscopic studies show that the domain wall density decreases with the addition of BiSc O3. The substitution of BiSc O3 also results in some no-phase-contrast areas in the domain structure image, which grow with the increasing BiSc O3 amount. Decent piezoelectric hysteresis loops were obtained in these areas. The correlation between the peculiar domain structure and relaxor behavior suggests that the no-phase-contrast areas are characteristics of the domain structure of the re-entering relaxor system. © 2008 American Institute of Physics.