Tunable equivalent dielectric constant and superior energy storage stability in relaxor-like antiferroelectric PLZT ceramic.

Pulse ceramic capacitors that request particularly high reliability and long lifetime forbid over-applied electric field, hence demanding high energy density (W re) and energy storage efficiency (η) at low electric field. In this work, we investigated a lead lanthanum zirconate titanate (PLZT) ceramic featuring both of tetragonal antiferroelectric phase (AFE T) and relaxor characteristic, which emerge in converged area of PLZT phase diagram (mole ratio of La reaches ~10%). Temperature dependent permittivity and XRD analysis proves the crossover trait in this structure. In this special relaxor-like AFE T structure, decent W re (1.2–1.3 J cm−3) and η (86–90%) are achieved at 12 V μ m−1. Equivalent dielectric constant (ε eq) is also introduced to illustrate nonlinear energy storage performance at different electric field. Compared to common dielectric materials, tunable ε eq in relaxor-like AFE T structure shows advantages of excellent low-field energy density and wide working span, leading to the convenience in size design of capacitors. Finally, good energy storage stability under various external field was verified: ~1.00 J cm−3 in W re and ~92% in η were stabilized under varied frequency (< ± 8.9%, 0.01–2000 Hz), temperature (< ± 9.8%, −60 to 120 ℃) and fatigue loading (< ± 9.8%, >108 times) at ~10 V μ m−1. [ABSTRACT FROM AUTHOR]