Study of Electrical Properties of Lead-free BCZT Ceramic (Ba0.80Ca0.20Zr0.1Ti0.9)O3 at Different Sintering Temperatures

Abstract

There is a tremendous growth in the demand for high performance lead-free ceramics due to environmental issues. In the present work, the traditional solid-state sintering technique at different sintering temperatures, namely, 1380, 1400 and 1420 ^oC has been employed to prepare lead-free (Ba_0.80Ca_0.20Zr_0.1Ti_0.9)O₃ ceramics. Detailed XRD analysis suggests pure perovskite structure for the ceramic synthesized at higher sintering temperature 1420 ^oC without any impurities. Density measurement using Archimedes principle shows a trend of increased densification with increasing sintering temperature. Room temperature frequency dependent dielectric constant study indicates high value of dielectric constant (ε_rt= 2665-2490) in the frequency range100 Hz-100 kHz for the ceramic sintered at 1420 ^oC. Temperature dependent dielectric studies at constant frequency (10 kHz) indicates that ceramic prepared at 1420 ^oC has high Curie temperature T_c =77 ^oC. Ferroelectric properties of the ceramics are enhanced by raising the sintering temperature from 1380 to 1420 ^oC with higher spontaneous polarisation of P_s = 7.68 μC/cm² corresponding to 1420 ^oC ceramic. The reasonably high values of Curie temperature, room temperature dielectric constant in the large frequency range and improved ferroelectric properties of the ceramic prepared at 1420 ^oC indicate that this ceramic can be a good candidate for being developed into commercially viable lead-free ferroelectric material.