A Study of Structural, Optical and Dielectric Properties of Crystalline Sr_2Nb_2O_7 Nanoparticles Synthesized by a Modified Combustion Technique

摘要

Nanocrystalline Strontium Pyroniobate is synthesized by a novel auto-igniting combustion technique. The XRay diffraction studies reveal that Strontium Niobate possesses orthorhombic structure. Phase purity and structure of the nanopowder is further examined using Fourier-Transform Infrared and Raman spectroscopy. The average particle size of the as prepared nanoparticles from the Transmission Electron Microscopy is 30 nm. Sr_2Nb_2O_7 is a photoluminescent material and the optical band gap determined from the UV-DRS spectrum is 2.7eV. The sample is sintered at an optimized temperature of 1350°C for 2 hours and obtained maximum density. The dielectric constant and loss factor values obtained at 5MHz for a well-sintered Strontium Niobate pellet is found to be 40 and 3.9x10~(-3) respectively, at room temperature.