Achieving both large piezoelectric constant and high Curie temperature in BiFeO3-PbTiO3-BaTiO3 solid solution

Abstract The high-temperature and high-performance piezoelectric ceramics are required urgently in the petrochemical, automotive, and aerospace industries. In this work, the (0.85-x)BiFeO3-xPbTiO3-0.15BaTiO3 (BF-PT-BT, x = 0.21, 0.22, 0.23, 0.24 and 0.25) piezoelectric ceramics with both high Curie temperature and large piezoelectric constant d33 were presented. X-ray diffraction analysis shows that BF-PT-BT ceramics exhibit dominant perovskite structure with the coexistence of tetragonal (T) and rhombohedral (R) phases. The c/a ratio, Curie temperature, piezoelectric constant, dielectric constant and loss of the BF-PT-BT ceramics for x = 0.23 are 1.06, 546 °C, 222 pC/N, 545 and 0.013, respectively. Room temperature piezoelectric constant of BF-PT-BT ceramics is much higher than those of PbTiO3, PbNb2O6 and other ABO3 perovskite compounds (BaZrO3, Bi(Zn, Ti)O3, PbZrO3 and Pb(Mg, Nb)O3) modified ternary BiFeO3-PbTiO3 ceramics with similar Curie temperatures. The piezoelectric constant is almost unchanged after BF-PT-BT ceramics was annealed at 450 °C for 30 min, which is due to the stable switched non-180° domain and transformed R phase by annealing treatment.