High depolarization temperature and large piezoelectricity in BiScO3–PbTiO3–Bi(Zn1/2Ti1/2)O3 piezoelectric energy harvesting ceramics†

Piezoceramics with a high depolarization temperature (T_d) and excellent piezoelectricity are ideal materials for constructing advanced high-temperature piezoelectric energy harvesters (HT-PEHs). Herein, the Bi(Zn_1/2Ti_1/2)O₃ (BZT) unit with a large tetragonality was added into the BiScO₃–PbTiO₃ (BS–PT) high-temperature piezoelectric matrix under the guidance of morphotropic phase boundary (MPB) manipulation and a lattice distortion modulation strategy. Based on the dual effects of linear expansion of MPB and the enhancement of lattice tetragonality, the perovskite-type 0.36BS–0.62PT–0.02BZT MPB composition shows a T_d of up to 418 °C and a large high-temperature piezoelectric constant (d₃₃) of 932 pC N⁻¹. The above comprehensive high-temperature characteristics are far superior to those of most reported perovskite piezoceramics. Moreover, the HT-PEH assembled using the 0.36BS–0.62PT–0.02BZT MPB ceramic exhibits excellent output power density of 80 μW cm⁻³ and ability to drive microelectronic devices even at 400 °C. This work demonstrates that the BS–PT–BZT material is a promising candidate for high-temperature piezoelectric energy harvesting applications.