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A magnetoelectric (ME) heterostructure was fabricated by depositing a Ni‐Mn‐Ga (NMG) magnetic film on an antiferroelectric (AFE) PLZST—(Pb, La)(Zr, Sn, Ti)O3—ceramic substrate. Significant and reversible electric field‐induced relative magnetization changes (∆M/M0) were firstly observed in this magnetic/AFE heterostructure, and the ∆M/M0 vs electric field loops have been found to correspond well with the strain‐electric field curve of PLZST ceramic. The maximum ∆M/M0 variation can reach 15%, indicating an obvious strain‐mediated converse magnetoelectric (CME) effect. A maximum CME coefficient of 1.14 × 10‐9 s/m was obtained at the switching electric fields of PLZST. The collected results suggest that AFE materials with a large electric‐field‐induced phase transition strain could be alternative candidates in ME coupling heterostructures. [ABSTRACT FROM AUTHOR]

Energy-storage properties of 0.89 Bi0.5Na0.5TiO3-0.06 BaTiO3-0.05 K0.5Na0.5NbO3 (0.89 BNT-0.06 BT-0.05 KNN) lead-free ceramics were first investigated. Measurements of dielectric properties together with switching current curves indicate a rather diffuse ferroelectric ( FE) to anti-ferroelectric ( AFE) phase transition when heating from 20°C to 90°C. The energy density ( W), which was calculated from P-E hysteresis loops, increases linearly with the external electric field when E exceeds AFE- FE transition field. W is independent of temperature and frequency, and maintains around 0.59 J/cm3 under 5.6 kV/mm in the stable AFE phase region. These properties indicate that 0.89 BNT-0.06 BT-0.05 KNN ceramics might be a promising lead-free AFE material for energy-storage capacitor application. [ABSTRACT FROM AUTHOR]

Abstract: The ferroelectric hysteresis loops of (1− x)BiScO3–xPbTiO3 (BSPT) ceramics with different phase structure were measured under sinusoidal electric fields. Three-stage behaviors between ln〈A〉 (〈A〉 is hysteresis loop area) and ln E 0 (E 0 is the amplitude of field) were identified with the increasing of E 0. These three-stage behaviors reflected different polarization behavior in each stage, which were distinct from the existing two-stage behavior. The shifting of dividing points between two stages with the evolution of phase structure revealed that in the tetragonal phase domain switching has a higher activation field due to the different domain structure. [Copyright &y& Elsevier]

Abstract Currently, there is an urgent need of extraordinary comprehensive pyroelectric materials for the wide application in detectors and energy harvesters. In this study, the (Pb 1–1.5 x La x)(Zr 0.86 Ti 0.14)O 3 (abbreviated as PLZT, x = 0.02, 0.03, 0.04 and 0.05) ceramics located in ferroelectric-antiferroelectric (FE-AFE) phase boundary were designed and synthesized by using conventional solid-state reaction method. The microstructures, phase structures, dielectric, ferroelectric, thermal depolarization and pyroelectric properties of the PLZT ceramics with different La content were investigated thoroughly. The XRD results show that the PLZT ceramics change from FE phase to AFE phase with increasing La content. The significant improvement of pyroelectric coefficient p and figures of merit (FOMs) are achieved in the PLZT ceramics with the increase in La content because of the increased metastable ferroelectric phase under the application of electric field. The (Pb 0.955 La 0.03)(Zr 0.86 Ti 0.14)O 3 (x = 0.03) ceramic exhibits not only high p of 5.2 × 10 − 8 C / cm 2 K and high depolarization temperature (T d) of 179 ℃ but also excellent FOMs with F i = 2.2 × 10 − 10 m / V , F v = 5.0 × 10 − 2 m 2 / C , and F d = 3.47 × 10 − 5 Pa − 1 / 2 . In addition, the highest p of 6.8 × 10 − 8 C / cm 2 K is achieved in (Pb 0.94 La 0.04)(Zr 0.86 Ti 0.14)O 3 (x = 0.04) ceramic. These results demonstrate that the PLZT ceramics of x = 0.03 and 0.04 are promising candidates for pyroelectric applications. [ABSTRACT FROM AUTHOR]