Structural, dielectric and ferroelectric studies of Ba1-xSrxTiO3 ceramics prepared by mechanochemical activation technique

In the present study, specimens of composition Ba1-xSrxTiO3 (x = 0.0, 0.05, 0.075, 0.10 & 0.15) were synthesized using mechanochemical activation technique and their structural, dielectric and ferroelectric characteristics were investigated for the major applications such as a multi-layered ceramic capacitor (MLCC) and microwave tunable devices. Structural analysis using X-ray diffraction pattern of the systems by Rietveld refinement confirms the formation of tetragonal phase with P4 mm space group. The intensity ratio of bonds and wave number shift in Raman spectra suggests little structural changes with strontium content. Microstructural investigation reveals that there is no appreciable change in grain size with increasing strontium concentration. The results on the variation of dielectric constant with temperature suggest the shifting of Curie temperature to lower temperature side with increasing strontium concentration. Current-voltage characteristics reveal that with increasing strontium content current increases which can be correlated with the observed variation of activation energy of the studied samples, which also decreases with the increasing concentration of strontium.