Ferroelectric Properties of Bi0.5(Na0.8K0.2)0.5TiO3 Ceramics

Different processing conditions and the effect of secondary phases on ferroelectric properties of Bi-0.5(Na0.8K0.2)(0.5)TiO3 (BNKT) are studied. Ceramic powders are prepared by solid state reaction and different sintering temperatures (temperatures between 1075 and 1150 degrees C) are analyzed. Finally, samples are characterized by X-ray diffraction, Raman micro-spectroscopy, scanning electron microscopy, impedance spectroscopy, and density measurements. Through XRD patterns, the perovskite structure is stabilized; together with small peaks corresponding to a secondary phase associated with K2-xNaxTi6O13 phase. Moreover, the content of the secondary phase, d(33) piezoelectric constant and dielectric properties increase with sintering temperature.