Large piezoelectricity and potentially activated polarization reorientation around relaxor MPB in complex perovskite

Improving piezoelectric performance is always favorable to further enhance the sensitivity and accuracy of piezoelectric devices. Here, a complex piezoelectric system of Pb(Ni 1/3 Nb 2/3 )O 3 -Pb(Yb 1/2 Nb 1/2 )O 3 -Pb(Hf 0.1 Ti 0.9 )O 3 is designed and investigated in detail. Optimized piezoelectric response of ∼ 880 pC/N is achieved at the composition of 0.51PNN-0.09PYN-0.40PHT. The characterization of TEM and In-situ high-energy synchrotron diffraction indicate that nanodomain growth and microdomain switching occurs in succession at around coercive electric field. Most interestingly, the coexisted tetragonal and rhombohedral-like phase transforms into multiple monoclinic-like phases with polarization vectors aligned as close to the electric field direction as possible under the strong electric field. The enhanced polarization instability in this complex morphotropic phase boundary sample should be ascribed to the strong local heterogeneity. The novel polarization rotation behavior found in this work would be important guidance for designing high-performance piezoceramics.