Lead-free Ba0.98Ca0.02Zr0.02Ti0.98O3 ceramics with enhanced electrical performance by modifying MnO2 doping content and sintering temperature

Abstract Lead-free Ba 0.98 Ca 0.02 Zr 0.02 Ti 0.98 O 3 -xmol% MnO 2 (BCZT-xMn) (x = 0.1, 0.2, 0.3, 0.4, 0.5) ceramics were prepared by conventional solid-state reaction method and the effects of MnO 2 doping content and sintering temperature on microstructure and electrical properties of BCZT ceramics were studied. The ceramics samples with all MnO 2 doping contents exhibit pure perovskite structure and similar Curie temperature of approximately 120 °C. Among all, the sample with 0.3 mol. % MnO 2 doping content sintered at 1400 °C exhibits improved ferroelectricity with a relatively high remnant polarization ( P r ) and low coercive electric field ( E c ) of 15.7 μC/cm 2 and 180 V/mm, respectively, which can be attributed to the fact that an appropriate doping content of MnO 2 does favor to the grain growth, with the favorable effect on domain motion. Accordingly, excellent piezoelectric property with piezoelectric coefficient ( d 33 ) of 308 pC/N can be obtained. Besides, the sample shows a relatively low dielectric loss (tanδ) of 1.04%. As a result, the BCZT-xMn ceramic exhibits the potential to be used in memory and transformer applications.