Structure, dielectric and ferroelectric properties of lead free (K,Na)(Nb)O 3 -xBiErO 3 piezoelectric ceramics

The effect of BiErO3 (BE) as a doping material on the structural, dielectric and ferroelectric properties of (KNa)NbO3 ceramics was explored in this research. Co-existence of two phase regions was confirmed in the composition range at x = 0.5% and x = 1.0%. The addition of BE content led to a decrease of the grain size and the ceramics became denser. Bulk P–E hysteresis loops were obtained with a maximum polarization of P max = 30.56 µC/cm2 and a remnant polarization of P r = 25.10 µC/cm2, along with a coercive field of E c ~ 11.26 kV/cm. The results revealed that a field strain value of ~ 0.26 for x = 0.5% of BE substitution was attained. This presents outstanding piezoelectric and dielectric properties.