Structural, optical and photoluminescence properties of K0.5Na0.5NbO3 ceramics synthesized by sol-gel reaction method

Potassium sodium niobate (KNN) ceramics have been prepared by sol-gel route. The effect of conventional sintering on its optical and photoluminescence properties has been studied. Optical measurements were done by reflectance measurements of the ceramics which showed decrease in optical band gap energy with an increase in sintering temperature. A room temperature photoluminescence (PL) spectrum was taken at an excitation wavelength of 300nm. The existence of green emission confirms the existence of oxygen vacancies in the sample. Raman spectroscopy analysis revealed changes in Raman scattering mode for KNN ceramics sintered at different temperatures. I-V characteristics have been studied from 20-180V disclosed that increase in sintering temperature favor higher order of leakage current at room temperature. [GRAPHICS] .