Optimized growth and electro-elastic properties of centimeter-sized piezoelectric crystals of Na2TeW2O9

Abstract

Large sized crystals of Na2TeW2O9 with dimensions up to 75 × 35 × 25 mm3 were successfully grown using an optimized top-seeded solution growth method. The as-grown Na2TeW2O9 single crystal exhibits well-developed faces with the major forms {200}, {002}, {202}, and {220}, which are in superior accordance with the ideal morphology predicted by the Bravais–Friedel and Donnay–Harker methods. A complete set of room temperature elastic, dielectric, and piezoelectric constants of Na2TeW2O9 single crystals was determined using resonance techniques and impedance analysis. Our results show that Na2TeW2O9 exhibits excellent piezoelectric properties (d15 = −23.93 pC N−1, d24 = −20.34 pC N−1), making the crystal a promising candidate for piezoelectric applications. The relationship between the piezoelectric properties and the crystal structure is also discussed.