Enhancement of piezoelectric and ferroelectric properties of BaTiO3 ceramics by aluminum doping

Ferroelectric and piezoelectric properties of BaTiO3 and Al-doped BaTiO3 ceramics were investigated. The ferroelectric study demonstrated that, by doping Al3+ ions in the A-site of BaTiO3, the polarization–electric field loop exhibited enhanced remnant polarization (from 12 to 17.5  μC/cm2), saturation and switching. In addition, the piezoelectric constant (d33) increased with Al-doping for both static and dynamic strain values (from 75 to 135 and from 29.2 to 57.9 pC/N, respectively, at a maximum applied electric field of 16 kV/cm). Furthermore, the dielectric constant values increased and both the dielectric loss factor and leakage current decreased, even though the transition temperature shifted to lower temperature (from 121 to 113 °C) for the Al-doped sample. Therefore, the Al-doped BaTiO3 has adjustable piezoelectric and ferroelectric properties.