Contribution of ferroelectric and nonferroelectric factors to D-E hysteresis loops of BiFeO3–BaTiO3 ceramics

Abstract Ferroelectric materials show the hysteresis phenomenon in response to external electric field stimulus owing to the nature of their domains. Hysteresis loops seem like a fingerprint of ferroelectric materials, and some useful pieces of information, such as coercive field, remanent polarization, and spontaneous polarization, can be extracted from hysteresis loops. Interestingly, even bananas can also apparently present an electric displacement–electric field (D-E) hysteresis loop. Therefore, various factors, such as domain switching, electric conductivity, and dielectric permittivity, can affect the ferroelectric properties and the shape of D-E hysteresis loops. In this study, the influence of ferroelectric and nonferroelectric factors on ferroelectric properties was investigated by preparing (1-x)BiFeO3-xBaTiO3-y mol MnO2 ceramics. Results showed that all D-E hysteresis loops had a gap. The gap was deduced to be relevant to the domain backswitching and capacitance of ceramics that can store and release charge during polarization. Moreover, the round D-E hysteresis loops were mainly attributed to electric conductivity. The 0.3BiFeO3–0.7BaTiO3–0.5 mol.% MnO2 ceramic exhibited outstanding electric properties, such as high Curie temperature (Tc = 538 °C) and optimal dielectric and ferroelectric properties (tanδ = 2.4 at T = 550 °C, Pr = 16.4 µC/cm2 at 150 kV/cm).