Improved piezoelectricity of lead-based PNN-PIN-PT ternary ceramics via polymorphic nanodomain modulation

High-performance piezoelectric materials are widely used in electromechanical applications such as sensors, actuators, and transducers. Herein, improvement in electrical properties of Pb(Ni 1/3 Nb 2/3 )O 3 −Pb(In 1/2 Nb 1/2 )O 3 −PbTiO 3 relaxor ferroelectrics by modulating the polymorphism of nano-scale domain is reported, and piezoelectric coefficients d 33 and d 33 * as high as 948 pC/N and 1108 pm/V, respectively, are achieved. The high piezoelectric response is elucidated by combining cryogenic dielectric , Rayleigh analysis, and scanning electron microscopy with piezoresponse force microscope. During the transition from the tetragonal to rhombohedral phase, the morphology of the ferroelectric domains changes significantly, mesoscopic domain destruction is observed, and thus nano-scale domains appear as an extrinsic contribution of piezoelectricity. In addition, nano-scale domains promote polarization rotation, thus, improving the piezoelectric response. The improved piezoelectric performance demonstrates good thermal stability, retaining the inverse piezoelectric coefficient of approximately 1000 pm/V near 70 °C. This work provides a good example of improving ceramics' piezoelectric response by modulating the polymorphism of nanoscale domains.