A new ternary ferroelectric crystal of Pb(Y1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3

Abstract

A ternary piezo-/ferroelectric crystal of 0.22Pb(Y_1/2Nb_1/2)O₃–0.44Pb(Mg_1/3Nb_2/3)O₃–0.34PbTiO₃ (PYN–PMN–PT (22/44/34)) with dimensions of 26 × 26 × 10 mm³ has been grown by the top-seeded solution growth (TSSG) method for the first time with the purpose of exploring new ferroelectric single crystals with high piezoelectric properties and was characterized by structural analysis and electrical measurements. The rhombohedral and tetragonal phases coexist in the as-grown crystals, which belong to the morphotropic phase boundary (MPB) region. The Curie temperature T_C and the rhombohedral–tetragonal phase transition temperature T_RT reached 125 °C and 90 °C, respectively. The dielectric constant ε′, dielectric loss tangent tan δ, piezoelectric coefficient d₃₃, longitudinal electromechanical coupling coefficient k₃₃, remnant polarization P_r and coercive field E_c were found to be 1280, 0.04, 1344 pC N⁻¹, 82%, 21.4 μC cm⁻², and 3.4 kV cm⁻¹, for [001]-oriented crystals at room temperature, respectively. These results show that the PYN–PMN–PT (22/44/34) crystals are a promising candidate for use in electromechanical transducer applications.