Synthesis, growth and characterization of potassium niobate (KNbO3) single crystal by top seeded solution growth method

Abstract

Potassium niobate (KNbO3), a lead free perovskite single crystal, was grown by top seeded solution growth method using K2 O as self flux. The synthesized powder and grown crystal of KNbO3 were studied by various characterization techniques. The thermal stability of KNbO3 was determined by Thermo Gravimetric and Differential Thermogram (TG-DTG) analyses. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Raman spectral studies reveal the formation of single phase orthorhombic structure of KNbO3 with space group Cm2m. In addition, Rietveld refinement analysis of XRD of KNbO3 confirms that there is no impurity or secondary phase formation in the grown crystal. Energy dispersive X-ray (EDS) analysis confirms the elemental composition and the presence of K, Nb and O. Chemical etching studies on the grown crystal reveal the layer by layer growth behavior.