Sol–Gel Synthesis and Characterizations for La_0.7Ca_0.15Pb_0.15CoO₃ Perovskite Cobaltite for Optical and Magnetic Applications

The thermal, microstructural, optical, and magnetic properties of La_0.7Ca_0.15Pb_0.15CoO₃ (abbreviated as LCPCO) cobaltite perovskite synthesized via sol–gel technique were investigated in this study. The TGA study reveals the completion of the crystallization pathway and the immediate formation of the sample. The obtained X-ray diffractogram with Rietveld refinement shows that the sample crystallizes in the rhombohedral structure with R3 ¯ c space group. Homogeneous particle distribution was observed from the SEM micrograph. From FTIR spectrum, LCPCO presents two absorption bands around ν₁ = 415 cm⁻¹ and ν₂ = 574 cm⁻¹ which are assigned to the O–Co–O bending vibration from the CoO₆ octahedra in LaCoO₃ perovskite, and Co–O stretching vibration, respectively. The UV–Vis absorbance spectrum reveals a remarkable visible-light absorption of the prepared sample with significantly lower band gap energy (E_gd = 1.549 eV). Additionally, significantly lower coercivity was observed, making the LCPCO perovskite cobaltite a promising candidate for recording media.