Structural and electrical properties of 0.98(K0.5Na0.5NbO3)-0.02(Bi0.5Na0.5TiO3) ceramics

Abstract

In the present communication, lead-free ceramics having composition 0.98(K0.5Na0.5NbO3)-0.02(Bi0.5Na0.5TiO3) were synthesized by a high-temperature solid-state reaction route. The Rietveld refinement for the 0.98KNN-0.02BNT reveals an MPB with phase fraction Amm2 (87.76 %) and Pm-3m (12.27%). The SEM study predicted a mean diameter of 0.98KNN-0.02BNT grains as 0.52 μm ± 0.19. The 0.98KNN-0.02BNTceramic displayed a typical hysteresis loop with a remnant polarization (Pr) of 7.0 μC⸳cm-2, saturation polarization (Ps) of 16 μC⸳cm-2, and a coercive field (Ec) of 26 kV⸳mm-1. The electrical, Raman spectra, dielectric, and hysteresis loop study supported a morphotropic phase boundary. The synthesized KNN-BNT lead-free material can be an excellent material for designing new devices like ultrasonic transducers and piezo-actuators. © 2023, Chulalongkorn University. All rights reserved.