Piezoelectric ceramics with high piezoelectricity and broad temperature usage range

There is a general observation that the Curie temperature and piezoelectric property of the ferroelectric ceramics can be enhanced only at the expense of each other, i.e., higher piezoelectricity, lower Curie temperature, thus, limits their applications over broad temperature range. In this research, Sm-modified 0.15 Pb(Mg_1/3Nb_2/3)O₃-(0.85-x)PbZrO₃-xPbTiO₃ ceramics have been studied, where excellent piezoelectric coefficients d₃₃ = 720 pC/N, d₃₃∗ = 950 pm/V and high Curie temperature T_C = 293 °C were simultaneously achieved for x = 0.42 composition by designing the morphotropic phase boundary (MPB) with local structural heterogeneity. Of particular significance is that a high thermal stability was observed with piezoelectric variation below 20% with temperature up to 280 °C, demonstrating that the x = 0.42 composition is a good candidate for piezoelectric application over broad temperature range where high temperature stability is required. This work provides a good paradigm for designing high-performance piezoelectric ceramics with high thermal stability via a combination of MPB and local structural heterogeneity.