Temperature-stable dielectric and energy storage properties of (0.94Bi0.47Na0.47Ba0.06TiO3-0.06BiAlO3)–NaNbO3 ceramics

Abstract The lead-free ceramics (1-x)(0.94Bi0.47Na0.47Ba0.06TiO3-0.06BiAlO3)-xNaNbO3 were prepared by means of a traditional solid-state sintering method. All ceramics have pure perovskite structure and average grain sizes around 1 μm. Their dielectric and energy storage behavior were studied. The NaNbO3-doped ceramics display drastically reduced temperature coefficient of capacitance (TCC) compared to the ceramics without doping. The samples with x = 0.02 exhibit high permittivity and excellent temperature stability between 67 °C and 380 °C, meeting the requirement of TCC ≤ ±15%. The energy storage density was greatly improved to 1.71 J/cm3 as x = 0.03, showing excellent frequency stability from 0.5 Hz to 100 Hz, great temperature stability from 25 °C to 130 °C, and excellent fatigue resistance within 105 fatigue cycles.