Piezoelectric properties and temperature stabilities of Mn- and Cu-modified BiFeO3–BaTiO3 high temperature ceramics

Abstract

Abstract The structures, microstructures, electrical properties and the thermal stability have been investigated for the MnO 2 -doped (1 − x )BF– x BT system and the MnO 2 and CuO-doped (1 − x )BF– x BT system, where x ranges from 0.25 to 0.35. The XRD analysis shows that the two systems have a single perovskite phase, and the MnO 2 and CuO-doped (1 − x )BF– x BT system has a morphotropic phase boundary (MPB) with the coexistence of rhombohedral and pseudo-cubic phases in the system about x = 0.325. The addition of small amount of CuO was quite effective to lower the sintering temperature. The diffusive phase transition characteristics were observed in the MnO 2 -doped (1 − x )BF– x BT system and a normal ferroelectric phase transition characteristics were observed in the MnO 2 and CuO doped (1 − x )BF– x BT system. Compared with the MnO 2 doped (1 − x )BF– x BT system, the ɛ m , Curie temperature ( T c ), depoling temperature ( T d ), and piezoelectrical properties were improved evidently with the MnO 2 and CuO doping.