Enhancement in the piezoelectric properties in lead-free BZT-xBCT dense ceramics

In this paper, we have prepared the lead-free piezoelectric BZT-xBCT (x = 0.48, 0.49, 0.50 and 0.51) polycrystalline compositions using solid-state reaction technique. Structural, microstructural and electrical properties were explored by changing the BCT concentration. Structural analysis shows the existence of morphotropic phase boundary in BZT-xBCT (x = 0.50) sample. The SEM micrographs illustrate the decrease in grain size with increase in the BCT concentration. The temperature-dependent dielectric behavior depicts high dielectric constant similar to 26,100 and low loss similar to 0.04 for BZT-0.48BCT composition at Curie temperature. The PE hysteresis loop shows the well-saturated hysteresis loops and low value of coercive field (E-C). The higher values of electromechanical planar coupling coefficient, K-P similar to 51.2%, piezoelectric coefficient, d(33) similar to 512 pC/N and bipolar strain (similar to 0.16%) were recorded for BZT-0.50BCT ceramic composition.