Breaking the piezoelectricity-coercivity trade-off via local multiphase nanodomain engineering

The pursuit of high-performance piezoelectrics is perpetually constrained by the inherent trade-off between a large piezoelectric coefficient ( d 33 ) and a high coercive field ( E C ); attaining one usually compromises the other. Here, we demonstrate a novel design strategy—local multiphase nanodomain engineering—to break this inverse relationship. In Eu 3+ -doped Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 (PMN-PT) relaxor ferroelectric single crystals, we achieve an exceptional combination of a giant d 33 of 3100 pC/N and a significantly enhanced E C . This contrasts with Nd 3+ -doped crystals, which exhibit a higher d 33 of 3300 pC/N but a reduced E C . Through atomic-resolution microscopy, we directly visualize that the smaller Eu 3+ ion promotes the formation of localized tetragonal (T) nanodomains, which act as pinning sites to increase E C , while the coexisting rhombohedral (R) and orthorhombic (O) matrices facilitate polarization rotation, enabling high d 33 . First-principles calculations reveal that the distinct electronic shielding effects of Eu 3+ and Nd 3+ dictate the anisotropy of local lattice distortions, steering the formation of different nanodomain structures. Our work transcends conventional doping effects, establishing a foundational strategy for designing advanced ferroelectrics with previously incompatible properties.