Simultaneously achieving giant piezoelectricity and record coercive field enhancement in relaxor-based ferroelectric crystals

A large coercive field (E(C)) and ultrahigh piezoelectricity are essential for ferroelectrics used in high-drive electromechanical applications. The discovery of relaxor-PbTiO(3) crystals is a recent breakthrough; they currently afford the highest piezoelectricity, but usually with a low E(C). Such performance deterioration occurs because high piezoelectricity is interlinked with an easy polarization rotation, subsequently favoring a dipole switch under small fields. Therefore, the search for ferroelectrics with both a large E(C) and ultrahigh piezoelectricity has become an imminent challenge. Herein, ternary Pb(Sc(1/2)Nb(1/2))O(3)–Pb(Mg(1/3)Nb(2/3))O(3)–PbTiO(3) crystals are reported, wherein the dispersed local heterogeneity comprises abundant tetragonal phases, affording a E(C) of 8.2 kV/cm (greater than that of Pb(Mg(1/3)Nb(2/3))O(3)–PbTiO(3) by a factor of three) and ultrahigh piezoelectricity (d(33) = 2630 pC/N; d(15) = 490 pC/N). The observed E(C) enhancement is the largest reported for ultrahigh-piezoelectric materials, providing a simple, practical, and universal route for improving functionalities in ferroelectrics with an atomic-level understanding.