Revealing the role of heat treatment in enhancement of electrical properties of lead-free piezoelectric ceramics

Abstract

The structural and electrical properties of the virgin, annealed, and quenched samples of 0.80BiFeO3–0.20BaTiO3 lead-free ceramics were investigated. The crystal structures investigated with the structure refinement method exhibited a rhombohedral structure for all the samples. The significant enhancement of ferroelectric and piezoelectric properties is ascribed to the relaxation of the lattice strain induced in the samples after the heat treatment. The bond-length calculated from the final structure refinement results revealed the increment of the A-O bond-length after the heat treatment, while the B-O bond-length was maintained in all the virgin, annealed, and quenched samples suggesting the specific influence of the lattice strain at the A-site of the material system.