Origin of high comprehensive electromechanical properties of novel donor and acceptor-codoped PMN-30PT ceramics

Donor and acceptor-codoped PMN-30PT ceramics with 1-3 mol% Sm and 1 mol% Mn were fabricated via a twostep solid-state reaction. The crystal structure and electrical properties were investigated in detail. Donor Sm and acceptor Mn codoping substantially enhances the electromechanical, piezoelectric, and dielectric properties with a high piezoelectric coefficient d33 = 483-680 pC/N, a high mechanical quality factor Qm = 518-642, a high field-induced strain = 0.20%-0.24 %, and a low dielectric loss tan 8 = 0.54%-0.69 %. X-ray diffraction and Raman spectra reveal the coexisting triple phase composition of the rhombohedral phase, tetragonal phase, and monoclinic polar nanoregions. Thermally stimulated depolarization current verifies the formation of various defect dipole clusters such as (Mn '' Ti-V & sdot;& sdot;O)x. With enhanced local structure heterogeneity induced by Sm, the phase composition and defect chemistry are regarded as the origin of such high comprehensive performance.