Giant high-temperature piezoelectricity in perovskite oxides for vibration energy harvesting

Abstract

By maintaining high piezoelectric coefficients (d₃₃), increasing the depolarization temperature is the key to constructing high-performance high-temperature piezoceramics. Unfortunately, so far, no piezoceramic has been found that still has a d₃₃ value above 700 pC N⁻¹ by in situ testing at a high-temperature of 400 °C. For popular 0.36BiScO₃-0.64PbTiO₃ ceramics with a MPB structure, the in situ quasi-static d₃₃ value at 400 °C is only 405 pC N⁻¹. Herein, a new strategy to enhance perovskite lattice distortion to obtain oxides with excellent high-temperature piezoelectricity has been proposed. By introducing Bi(Zn_0.5Hf_0.5)O₃ to enhance lattice distortion of a (1 − x)BiScO₃-xPbTiO₃ matrix, a ternary system zBiScO₃-xPbTiO₃-yBi(Zn_0.5Hf_0.5)O₃ (zBS-xPT-yBZH) was designed. A record-high in situ quasi-static d₃₃ value of 726 pC N⁻¹ at 400 °C is achieved in a 0.355BS-0.635PT-0.01BZH composition. Structural analysis confirmed that the introduction of highly tetragonal Bi(Zn_0.5Hf_0.5)O₃ can enhance the lattice distortion and the sample annealed at 400 °C still maintains a stable domain configuration. Moreover, a high-temperature piezoelectric energy harvester is manufactured from the optimal material, and exhibits excellent high-temperature power generation capacity, and a 10 μF commercial electrolytic capacitor can be easily charged to 0.9 V in 40 s at 400 °C. This work demonstrates that zBS-xPT-yBZH ceramics have great potential for application in extreme high temperature environments, and pave the way for obtaining high-quality high-temperature piezoelectric materials.