Frequency dependence of antiferroelectricferroelectric phase transition of PLZST ceramic

Abstract

Antiferroelectric (AFE) ceramics are promising for applications in high-power density capacitors, transducers, etc. The forward switching field (𝐸 AFE−FE ) and backward switching field (𝐸 FE−AFE ) are critical performance indicators for AFE ceramics, and the coupling between the structure transition and domain orientation makes them different from the coercive field (𝐸 C ) of ferroelectric (FE). Moreover, in practical applications, AFE ceramics are often required to operate at varying frequencies. However, systematic studies regarding the frequency dependence of 𝐸 AFE−FE and 𝐸 FE−AFE are insufficient. In this work, Pb 0.98 La 0.02 [(Zr 0.55 Sn 0.45 ) 0.88 Ti 0.12 ] 0.995 O 3 (PLZST) AFE ceramic was fabricated, and two empirical formulas (𝐸 AFE−FE = 𝐴+𝐾 𝐴 × 𝑓 𝛽 , 𝐸 FE−AFE = 𝐹−𝐾 𝐹 × 𝑓 𝛽 ) were proposed to predict the frequency dependence of 𝐸 AFE−FE and 𝐸 FE−AFE .The formulas are based on the electric field-induced phase transition characteristics of AFE and the Kolmogorov-Avrami-Ishibashi domain nucleationswitching model. Furthermore, the dynamic hysteresis loops of PLZST at various frequencies (1-1000 Hz) and temperatures (30-230 • C) were investigated. The results show that the electric field-induced phase transition of AFE ceramic is dominated by the coupling between the structural transition and domain orientation. The domain orientation hinders the structure transition, leading to an increase in 𝐸 AFE−FE and a decrease in 𝐸 FE−AFE as the frequency of applied electric field increases. Meanwhile, the domain growth process is affected by the structure of AFE, and the value of 𝛽 (domain growth dimensionality) increases with the stability of the AFE structure. For comparison, Pb 0.86 La 0.02 Ba 0.12 [(Zr 0.55 Sn 0.45 ) 0.88 Ti 0.12 ] 0.995 O 3 (PLBZST) relaxor FE ceramic was fabricated. Due to the high mobility of the microdomain, the dynamic hysteresis loop of PLBZST ceramic exhibits excellent frequency stability. The charge-discharge experiment with an ultrahigh equivalent frequency (𝑓 equivalent >100 kHz) was performed to investigate the frequency stability of energy release of PLZST and PLBZST. The results may provide guidance for research pertaining to ceramic capacitors with high-power density and highfrequency stability.

Ultrahigh Energy Storage Density and Efficiency in Orthorhombic PLZST Antiferroelectric Ceramics via Composition Regulation

“…When the temperature is below 60 °C, the splitting peak near 44.5° becomes prominent, and the XRD pattern exhibits an AFE O-phase structure corresponding to a P – E loop with high polarization intensity and a high energy storage density. When the temperature ranges between 60 and 140 °C, although the XRD pattern still displays characteristics of the splitting peak, there is a transition in the phase structure to an AFE T-phase, which corresponds to a curve with high energy storage efficiency. , As the temperature exceeds 140 °C, the splitting peak starts merging, indicating that multiple phases coexist in a PE MCC state. Upon reaching 300 °C, the splitting peak completely transforms into a unimodal peak, signifying a pseudocubic structure.…”

Antiferroelectric PbSnO3 Epitaxial Thin Films

“…At high‐temperature regimes, such as 110 °C, the AFE and MCC phases coexist in PSO thin films. [ 38 , 39 ] In the P – V measurement, the randomly arranged domain wall between these two phases causes some irreversible motion and makes the hysteresis loop break down. Hence, it is the reason to adopt higher frequency at high temperatures to freeze the motion of the domain wall.…”