Composition dependent structure, dielectric and energy storage properties of Pb(Tm1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3 antiferroelectric ceramics

In order to stabilize the perovskite structure and improve the storage energy density (U) of Pb(Tm1/2Nb1/2)O3 (PTmN) based materials, Pb(Mg1/3Nb2/3)O3 (PMN) was introduced into PTmN to form binary (1-x)PTmN-xPMN solid solution ceramics. The XRD patterns show that all the compositions belong to orthorhombic phase with space group Pbnm. The Curie temperature (TC) gradually decreases while the dielectric constant (ε') increases for (1-x)PTmN-xPMN with increasing PMN content. The ε' of each composition above TC obeys the Curie-Weiss law. The appearance double hysteresis loop confirms the antiferroelectric nature of (1-x)PTmN-xPMN (x = 0.02-0.18) ceramics. With the increase of PMN concentration, the maximum polarization slowly increases from 8.58 μC/cm2 to 29.5 μC/cm2 while the threshold electric field (EA-F) gradually declines from 290 kV/cm to 120 kV/cm. The maximum of U (3.12 J/cm3) is obtained in 0.92PTmN-0.08PMN ceramic with moderate EA-F = 220 kV/cm, which makes (1-x)PTmN-xPMN ceramics safe in practical application.