Enhanced Electrostrain at Low Driving Electric-Field with the Dual-Phase Coexistence Assisting

Piezoelectric ceramics, which are a vital type of driving component in electronic actuators, commonly require a high driving electric field to obtain a large electric field-induced strain due to their high coercive field. However, the piezoelectric ceramics with high coercive fields are difficult to apply in practical products. Therefore, it is of significant importance to develop a type of piezoelectric ceramic with a large electric field-induced strain and low hysteresis under a low driving electric field. In this work, we successfully prepared the (1–x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 ceramics with a low driving electric field. An ultrahigh piezoelectric strain coefficient d33* of 1205 pm/V, a superior piezoelectric constant d33 of 810 pC/N, and an outstanding planar electromechanical coupling coefficient kp of 0.7 are achieved. These superior electrical properties are attributed to multiphase and local polar nanoregions’ coexistance, which have been verified by Rietveld refinement and TEM. These findings will provide a feasible path to develop high-performance piezoelectric materials.