Capacitive and Resistive Properties of Molten Salt Synthesized Lead-Free K1/2Na1/2NbO3 Ceramic.

Lead-free K_1/2Na_1/2NbO₃ (KNN) powder was synthesized using the molten-salt process in the eutectic mixture of KCl–NaCl at a low temperature of 700 ℃ for 2 h, which is less than that of the widely used conventional technique solid-state synthesis. X-ray diffraction (XRD) was used to investigate the purity and phase formation. To characterize the surface morphology of sintered ceramics, scanning electron microscopy (SEM) is used. The studies of dielectric permittivity and impedance spectroscopy were performed ranging from 1 Hz to 1 MHz on KNN at temperatures ranging from room temperature (RT) to 580 ℃. The piezoelectric coefficient constant d₃₃ of KNN was obtained, and it is 90 × 10⁻¹² pC/N. Nyquist plots of complex impedance were used to deduce the mechanism of relaxation. These plots depict non-Debye relaxation behavior. The conductivity contributions of grain and grain boundary were estimated using Cole–Cole plots. In addition, antibacterial activity for the KNN was tested using a four-plate approach. [ABSTRACT FROM AUTHOR]