High temperature stability “Li+–Al3+” co-doped BaTiO3 piezoelectric ceramic

Li+ and Al3+ co-doped BaTiO3 ceramics were prepared by the conventional high-temperature solid reaction. The piezoelectric coefficients of the BaTiO3-based ceramics were obtained from room temperature to the Curie temperature. The influence of doping content on the temperature stability of the doped BaTiO3 ceramics was also discussed. From the X-ray diffraction results, we inferred that the Li+–Al3+ ion pairs preferentially oriented along the [001] direction, the main direction of lattice distortion. After co-doping, the piezoelectric properties of the BaTiO3-based ceramics became more temperature-stable. The d33 piezoelectric coefficient remained high below the Curie temperature (TC ≈ 125 °C). After normalizing the data, we observed that the BaTiO3-based ceramic doped with 2 mol