Growth and electrical properties of Na1/2Bi1/2TiO3–BaTiO3 lead-free single crystal with morphotropic phase boundary composition

Abstract

In present work, lead-free single crystal 0.94Na1/2Bi1/2TiO3–0.06BaTiO3 (NBBT94/6) with dimension of Φ40 mm×10 mm was grown by a precisely controlled top seeded solution growth method. The crystal structure measurement result indicates that the NBBT94/6 single crystal exhibits the feature of rhombohedral-tetragonal phase coexistence at room temperature. The crystallographic orientation dependence of electrical properties for NBBT94/6 single crystal was investigated in detail. The remnant polarizations (Pr) of ⟨001⟩, ⟨001⟩, and ⟨111⟩ oriented crystals are 16.02 μC/cm2, 22.16 μC/cm2, and 27.23 μC/cm2, respectively. The corresponding coercive fields (Ec) are 24.89, 20.72, and 15.36 kV/cm. Moreover, a double hysteresis loop appears at the depolarization temperature. High piezoelectric properties d33 of 360 pC/N and kt of 62% were obtained in the ⟨001⟩ oriented crystals due to the engineered domain configuration which make them promising candidates for environmental friendly solid-state actuator applications.