Multiphase coexistence and enhanced electrical properties in (1-x-y)BaTiO3-xCaTiO3-yBaZrO3 lead-free ceramics

In this work, the multiphase coexistence of rhombohedral-orthorhombic and orthorhombic-tetragonal (R-O/O-T) was constructed in (1-x-y)BaTiO3-xCaTiO3-yBaZrO3 ceramics with 0.14 ≤ x ≤ 0.16 and 0.10 ≤ y ≤ 0.12, and thus a large piezoelectric constant (d33) of 600 pC/N was attained in the ternary (1-x-y)BaTiO3-xCaTiO3-yBaZrO3 ceramics using the optimization of x and y. The R-O/O-T multiphase coexistence as well as the enhancement of dielectric and ferroelectric properties can be responsible for the high d33 of this work. In addition, a high strain of 0.15% was observed in the multiphase coexistence. As a result, electrical properties of BaTiO3 can be optimized by the construction of multiphase coexistence through the co-doping of CaTiO3 and BaZrO3.