Effect of calcium doping on LaCoO3 prepared by Pechini method

Calcium doped lanthanum cobaltite (La1 − xCaxCoO3) (x = 0, 0.2, 0.4, 0.6, 0.8) with different concentrations has been prepared by modified Pechini type polymerizable method. The X-ray diffraction pattern of the calcium doped samples shows the formation of perovskite material in cubic structure. Scanning electron and transmission electron microscopic analysis shows the porous nature of the prepared material. The appearance of peak at 347.5 eV for calcium confirms its presence in the doped samples. Conductance spectra analysis reveals the frequency independent behavior of the samples and the conductivity is related with the particle size. The sample doped with 0.6% of calcium is found to show high conductivity. The temperature dependent conductivity indicates Arrhenius type behavior.

Pechini method is used to prepare lanthanum cobaltite doped with calcium. Increasing the calcium doping level leads to a change in structure from rhombohedral to cubic. Compositional analysis confirms the calcium incorporation in lanthanum cobaltite. Electrical analysis confirms the increase in conductivity with increasing calcium level and semi-conducting behavior of the prepared samples.Figure optionsDownload as PowerPoint slideHighlights
► Calcium doped lanthanum cobaltite by Pechini method
► Increase in formation temperature with increasing calcium content
► Change in structure from rhombohedral to cubic with calcium doping
► Morphological analysis reveals the porous nature of the materials.
► Electrical analysis reveals mixed conducting behavior.