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In this paper, we prepared lead-free (1-x)BaTiO 3 -xBi(Zn 0.5 Ti 0.5 )O 3 (x=0.04, 0.08, 0.10, and 0.14) ceramics by a conventional solid-state reaction technique. Pure perovskite structures and dense microstructures were demonstrated for all the compositions. Interestingly, it was found that the sintering temperature tended to decrease with increasing the Bi(Zn 0.5 Ti 0.5 )O 3 content. It should be stressed that a low sintering temperature of 1050 °C was utilized for the composition of x=0.14. Moreover, the dielectric permittivity-temperature curve became more flat and the relaxor degree became stronger with the augment in Bi(Zn 0.5 Ti 0.5 )O 3 content. We also conducted a detailed study on the energy storage performance for all the compositions from 25 °C to 180 °C.We found that relatively temperature-stable energy storage performance could be obtained in the compositions with x=0.08, 0.10 and 0.14 regardless of the evolution of dielectric constant during the test temperature range. In particular, due to a higher field of 12 MV m −1 , the discharge energy storage densities of x=0.14 could reach 0.81 J cm −3 , 0.80 J cm −3 , 0.78 J cm −3 , 0.72 J cm −3 , and 0.67 J cm −3 with high efficiencies of 94%, 92%, 94%, 88% and 77% at 25 °C, 50 °C, 100 °C, 150 °C, and 180 °C, respectively. All these results demonstrate the (1-x)BaTiO 3 -xBi(Zn 0.5 Ti 0.5 )O 3 ceramics are quite promising for temperature-stable energy storage applications. [ABSTRACT FROM AUTHOR]

The fatigue behavior of 0.05Pb(Mn 1/3 Sb 2/3 )O 3 –0.50PbZrO 3 –0.45PbTiO 3 ceramics (abbreviated as PMS-PZT) is investigated. Special attention is paid to the effect of applied electric frequency on the evolution of polarization-electric field, strain-electric field hysteresis loops as well as the parameters of remnant polarization, internal bias field and coercive field extracted directly from the former hysteresis loops or calculated according to these loops. It is found that the fatigue behavior is different from that of donor doped Pb(Zr,Ti)O 3 (PZT) ceramics demonstrated by the tendency of increasing remnant polarization, the decreased internal bias field, decreased asymmetry of polarization-electric and strain-electric loops with increasing fatigue duration when PMS-PZT ceramics fatigued at lower frequency (i.e. 5 Hz or 500 Hz). The dynamic of oxygen vacancies under the application of bipolar electric field is supposed to be associated with the abnormal fatigue behavior. In addition, no matter at which cyclic frequency samples fatigued, coercive field shows the tendency of decrease with increasing fatigue duration except for sample fatigued at 5 kHz in which coercive field first decreases and then increases. According to phase structure and the empirical Rayleigh analysis, phase transition during fatigue treatment is supposed to be account for the decrease of coercive field. [ABSTRACT FROM AUTHOR]