ZnTa2O6-holistic insights into a potential high-temperature piezoelectric candidate with tri-alpha-PbO2 structure

Abstract

We have comprehensively investigated the structural, morphological, vibrational, thermal, and surface charge properties of ZnTa2O6 (ZTO) system, which is predicted to be a novel, lead-free, high-temperature piezoelectric candidate. Single-phase polycrystalline samples were formed having orthorhombic Pbcn symmetry with the tri-alpha-PbO2 structure. ZTO was highly Raman active, expressing higher electronically excited states of even parity and with the presence of far-IR modes. The crystallization of ZTO was observed at-691 degrees C with a melting enthalpy, Delta Hm =-301.7 J/g. Force-driven dielectric constant (epsilon r) was found to be 7.05 with an ultra-low loss tangent value of 1 x 10-4 at 0.45 N dynamic force. Energy storage efficiency of 43% at 5 kV/cm and a piezo-electric charge coefficient (d33) value of 20 pC/N were obtained. The confluence of all these properties makes ZTO a novel piezoelectric material with high-temperature stability whilst further evoking applications in energy harvesting, electronics, memory storage, and electromechanical systems.