Top-seeded solution growth and characterization of PMN–0.31PT piezoelectric single crystals

Piezoelectric single crystals of 0.69Pb(Mg1/3Nb2/3)O3–0.31PbTiO3 were grown by a top-seeded solution growth method that prevented phase segregation and promoted the (001)-growth. The morphotropic phase boundary (MPB) structure was confirmed by X-ray diffraction and the dielectric, piezo- and ferro-electric properties were characterized. A dispersive maximum of dielectric permittivity appears around TC = 135 °C, which slightly shifts towards higher temperatures with increasing frequency, indicating weak relaxor behaviour. The rhombohedral–tetragonal phase transition was detected at 108 °C. The piezoelectric coefficient (d33) was found to be 2080 pC N−1, with a strain level reaching 0.17% at an electric field of 10 kV cm−1. The longitudinal electromechanical coupling factor k33 reaches 92%.