Abstract
Sr-doped lanthanum cobaltite (La1−xSrxCoO3) perovskite oxides with × = 0.0, 0.20, 0.50, 0.80 were prepared using the modified sol–gel method at 600 °C. The synthesized Sr-doped LaCoO3 perovskite oxides (x = 0.0 and 0.20) crystalize as rhombohedral structured materials, while La0.2Sr0.8CoO3 perovskite oxide (x = 0.80) crystalizes as primitive cubic structured material as also confirmed by Rietveld refinement using x-ray diffraction. Moreover, the synthesized materials were investigated in details using fourier-transform infrared spectroscopy, scanning electron microscopy, energy dispersive studies and x-ray photoelectron spectroscopy techniques. The electrical conductivity of the perovskite oxides was improved through the substitution of La by Sr. Frequency dependent dielectric properties (dielectric constant and dielectric loss) of La1−xSrxCoO3 perovskite oxides were also investigated in frequency range from 20 Hz to 3 MHz at room temperature. Dielectric constant and dielectric loss of La1−xSrxCoO3 perovskite oxides decrease at low frequency, while it was found to be constant at high frequency.