Super-broad temperature stability achieved by la-doped BaTiO3–Bi0.5 Na0.5TiO3–Nb2O5 based ceramics

BaTiO3–Bi0.5Na0.5TiO3–Nb2O5–ZnO–Glass ceramics with La2O3 addition, were prepared and studied to satisfy super-broad temperature stability (from −55 to 325 °C, capacitance variation rate based on C20°C is within ±15 %). With the addition of 0.4 mol% La2O3, a remarkable high ceiling working temperature of 325 °C has been achieved. Meanwhile, the sample has good dielectric and electrical properties at room temperature (er = 2,121, tanδ = 1.82 %, ρV = 1.63 × 1011 Ω cm). La iron can substitute for Ti iron as La3+. The substitution decreases the spontaneous polarization of BaTiO3, and then weakens the ferroelectricity of BaTiO3. As a result, the temperature stability of the samples is improved obviously. The maximum of TCC value was reduced from 24 to only 7 % by doping 0.4 mol% La2O3. This substitution also gave rise to the densification of the system.