Study of structural and magnetic properties of Sn-doped cobaltite perovskite LaCoO₃: experimental and DFT approach

The cobaltite perovskites LaCo_1−xSn_xO₃ (x = 0.00, 0.03, 0.06, 0.09, and 0.12) were synthesized using the conventional sol–gel technique. The effect of Sn doping on the structural, magnetic, and dielectric properties of LaCoO₃ has been studied. XRD and Rietveld's refinement revealed structural details of rhombohedral crystallized pure LaCoO₃ compound. However, Sn doping resulted in Sn ions occupying Co sites, and resultantly, the crystal structure adopted an orthorhombic structure, which was also verified using density functional theory-based computations. The surface morphology studied using SEM revealed that Sn doping increases grain size. EDX study revealed the presence of the constituent elements (La, Co, O, and Sn). FTIR spectra showed the presence of O–Co–O bonds due to the CoO₆ octahedron and confirmed the characteristic ABO₃-type perovskite structure. VSM measurements at room temperature showed that increasing Sn content from x = 0.00 to 0.09, the remnant magnetization enhanced from 0.002 to 0.018 emu/g, while it declined to 0.015 emu/g at x = 0.12. The role of La and Co ions in the total magnetization and the underlying exchange mechanism was also explained using the computed results. The Sn doping in LaCoO₃ resulted in improved magnetic properties, which revealed potential commercial use in data storage-related device applications.