Temperature-dependent neutron diffraction study of phase separation at morphotropic phase boundary in (1−x)BiScO3–xPbTiO3

Abstract

We report the results of temperature-dependent neutron powder diffraction experiments on (1−x)BiScO3–xPbTiO3 (x=0.62, 0.64, and 0.66) within the morphotropic phase boundary. In all samples the monoclinic phase is found to coexist with the tetragonal phase below the ferroelectric transition temperature. The details of structural information demonstrate a delicate balance between the coexisting two phases for x=0.64. Such delicate balance is suggested to be sensitive to an external electric field, thus responsible for the enhanced electromechanical properties observed for x=0.64. Our result reveals that phase separation and the delicate balance between two phases are crucial to understand the unique properties at the morphotropic phase boundary in (1−x)BiScO3–xPbTiO3 ferroelectric systems.