Characterization of dielectric and piezoelectric responses in 0.76(Na0.5Bi0.5)TiO3-0.06BaTiO3-0.18(K0.5Bi0.5)TiO3 ceramics synthesized by the solid-state method.

In this research, the authors explore the structural, dielectric, electrical insulating, electromechanical, and piezoelectric characteristics of ceramics that have been modified using BaTiO 3 and (K 0.5 Bi 0.5)TiO 3.as key components. Specifically, they explore the composition (1-x-y)(Na 0.5 Bi 0.5)TiO 3 -xBaTiO 3 -y(K 0.5 Bi 0.5)TiO 3 , where x (mol.%) varies between 0, 6, and NBT, and y (mol.%) varies between 0, 18, and KBT. These ceramics were fabricated using a solid-state synthesis technique. The optimized calcination temperature for achieving a pure perovskite phase was determined to be 1000 °C for a duration of 4 h. The research involves a comprehensive analysis of the composition, microstructure, electrical insulating, and electromechanical characteristics of the ceramics. Rietveld analysis of X-ray diffraction (XRD) data was employed to accurately ascertain the morphotropic phase boundary (MPB) within this material. In this paper, we discuss the impact of crystallite size on the shifts in Raman band frequencies. Sintering at 1100 °C for 4 h was found to enhance densification, with scanning electron microscopy (SEM) images illustrating a nearly uniform distribution of compact grains. Electrical insulating assessments demonstrate that each of the ceramics displays a scattered phase transition around the temperature T m , with a diffusivity ranging from 1.4 to 1.8, and a shift of T m towards elevated temperatures. Exceptional piezoelectric properties were observed at the morphotropic phase boundary (MPB), including a d 33 value of 149 pC/N and electromechanical coupling factors kp of 0.297. These findings are attributed to the coexistence of rhombohedral and tetragonal phases, as well as precise grain size control. This research presents a novel approach to enhancing lead-free ferroelectric materials based on the composition 0.76(Na 0.5 Bi 0.5)TiO 3 -0.06BaTiO 3 -0.18(K 0.5 Bi 0.5)TiO 3. [ABSTRACT FROM AUTHOR]