Electrical and Ferroelectric Properties of Strontium Doped Lead-Free BCZT Ceramics

Herein, we synthesized Ba0.9-xCa0.1SrxTi0.8Zr0.2O3(x = 0.05, 0.1, 0.15, 0.2) ceramic samples by employing a solid-state reaction technique. The variation of dielectric constant is studied concerning temperature in the range 1 kHz to 1 MHz frequency. Variation of dielectric constant ( ) with temperature reveals that charge carrier dispersion pushes the transition temperature towards higher frequency. Impedance analysis reveals that the maximum value of the imaginary part of impedance i.e., maxima, increases in all samples except for x = 0.05, which shows the opposite behaviour. This behaviour is due to the calcium (Ca2+) substitution at the titanium (Ti4+)-site at low doping concentration of Sr2+ ions. Nyquist plots show the presence of a single semi-circular arc, indicating the contribution of resistance and capacitance through grain boundary. PE hysteresis loops reveal that the values of saturation polarization ( ) decrease with increasing Sr-doping, from 10.989 μC cm−2 to 6.586 μC cm−2, whereas the remnant polarization ( ) shows variable values with increasing Sr-doping.