Effects of compositional modification in lead lanthanum zirconate stannate titanate ceramics on electric energy storage properties

摘要

The effects of compositional modifications on the antiferroelectric (AFE) to ferroelectric (FE) transition of lead lanthanum zirconate stannate titanate, (Pb_(1-3x/2)La_x)(Zr_(1-v-z)Sn_vTi_z)O_3, ceramics were used to optimize this material for energy storage. The experimental results show that an increase of Sn~(4+) with respect to Ti~(4+) increases the coercive field of AFE-FE transition and keeps the hysteresis at the minimal level. This increases both the energy density of material and energy efficiency relative to a linear dielectric. Another advantage of Sn~(4+) addition was a polarization increase at the switching field. The substitution of Zn~(4+) for Sn~(4+) at fixed Ti~(4+) concentration of 0.1 was, however, undesirable for energy storage applications since this decreased the forward switching field and increased the hysteresis. This lowered both the energy density of the material and energy efficiency. Finally, addition of La~(3+) was performed and slim hysteresis loops were obtained resulting in energy efficiency of 80.1%. However, the slanted hysteresis behavior with La~(3+) results in a lower value of the maximum stored energy.