Synthesis of Nano-Structured Strontium Titanate by Sol-Gel and Solid State Routes

Abstract

In this paper strontium titanate SrTiO₃ nanopowders were synthesized via sol-gel and solid state methods with the aim of exploring the influence of the synthesis process on the obtained material. SrTiO₃ powders were characterized by different spectroscopic and microscopic techniques, such as x-ray diffraction (XRD), infrared (IR), thermogravimetric analysis (TGA) and differential thermal analysis (TGA-DTA), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The magnetization and the dielectric characteristics of the synthesized SrTiO₃ were demonstrated. XRD results revealed the formation of SrTiO₃ and SrTiO₃ with anatase TiO₂ by solid state and sol-gel methods, respectively. The synthesis of SrTiO₃ by the solid state route led to the formation of microcrystalline particles. However, the sample prepared by the sol-gel method was more homogenous containing very fine particles with sizes in the nanometer regime. The TEM investigation showed the formation of nanoparticles with an average size of about 10 nm. The sol-gel synthesized sample exhibited a higher magnetization compared with the solid state synthesized one. The values of the dielectric of constants sol-gel synthesized samples are higher than those of the samples prepared by the solid state method.