Improvements of physicochemical properties of K0.5Na0.5NbO3 ceramics by addition of selected chelating agents.

In this paper, K 0.5 Na 0.5 NbO 3 (KNN) samples were successfully synthesized via modified Pechini technique with many different chelating agents. Physicochemical studies as differential scanning calorimetry (DSC) measurements, dielectric measurements, impedance spectroscopy and structural analyses confirmed the influence of chelating agent on phase transformation from the ferroelectric orthorhombic to tetragonal and ferroelectric tetragonal to paraelectric cubic phase. The study of the charge transfer mechanism of KNN is carried out based on small polaron hopping theory. In addition, the high dielectric constant associated with a low dielectric loss observed for KNN material obtained using combination of glycine and oxalic acid makes it a possible use in electronic devices. [ABSTRACT FROM AUTHOR]