High temperature piezoelectric strontium bismuth titanate from mechanical activation of mixed oxides

Perovskite strontium bismuth titanate (SrBi4Ti4O15, SBIT) of layered structure has been successfully prepared via mechanical activation of mixed oxides of SrO, Bi2O3 and TiO2 for more than 15 h at room temperature. The mechanical activation-derived SBIT can be sintered to a relative density of ∼98% theoretical at 1175 °C which exhibits a maximum dielectric constant of 2770 at the Curie temperature ∼539 °C when measured at 100 kHz. The conductivity of sintered ceramic was studied using an impedance spectroscopy. An activation energy of 0.22 eV is observed at low temperatures and it increases with increasing temperature. A piezoelectric coefficient, d33, of 24.0 pC N−1 is measured at room temperature for sintered SBIT.