Simultaneously enhanced piezoelectric response and Curie temperature in rhombohedral BS–PT ceramics by Zr doping

•It is firstly found the d33 and TC are simultaneously increased in BS-PT system.•Our results break the general rule that the d33 always increases at the expense of TC.•The ceramics show the high d33 ∼ 440 pC/N, kp = 53%, εr ∼ 1600, and tc ∼ 440 °C.•The d33 is 68% higher than the previous reported 260 pC/N.•The T + R + M phase coexistence plays a key role for excellent properties. This is the first study that proves that Curie temperature (Tc) and piezoelectric properties can be simultaneously improved in a (1-x)BiScO3-xPbTiO3 [(1-x)BS-xPT] system, which is different from the general rule that piezoelectric properties of the Pb-based piezoceramics always increase at the expense of Tc. The lead-poor 0.39BS-0.61PT composition was chosen as the parent material beyond the morphotropic phase boundary. The Zr-doping effects on the structure and properties of ceramics were investigated. With the ZrO2 increment, the single rhombohedral phase was gradually transformed into the tetragonal + rhombohedral + monoclinic multiphase coexistence. The piezoelectric coefficient (d33) was increased to 436 pC/N, which was 68% higher than that of the previously reported 260pC/N. More importantly, the Tc of ceramics also increased from 410 °C to 440 °C with the ZrO2 increment. Our results suggest that a certain BS–PT composition may simultaneously yield excellent piezoelectric properties and a high Tc. [Display omitted] Figure (a) shows the relationship between piezoelectric constant d33 and Curie temperature (Tc) for various piezoelectric materials doped by different mental ions doping. Clearly, the piezoelectric coefficient for the PZT, 0.69PMN-0.31PT, and 0.36BS-0.64PT piezoceramics always increases at the expense of Curie temperature. Therefore, it is generally believed that the piezoelectric properties of PT-based piezoelectric ceramics are incompatible with Curie temperature. However, our results show in the inset of figure (a) that ZrO2 doping can enhance simultaneously the piezoelectric response and Curie temperature for the certain 0.39BS-0.61PT composition outside of MPB region, which is attributed to the transformation of phase structure from the rhombohedral (R) phase to the multiphase coexistence of tetragonal (T)+ rhombohedral (R)+monoclinic (M) with the increase of ZrO2, as shown in figure (b).