Structural, Magnetic, and Magnetocaloric Effects of La0.8Sr0.2MnO3 Manganites by Doping with f-Orbital Ions Through First-Principles Calculations

In this study, La 0.63 Sr 0.2 Nd 0.17 MnO 3 was synthesized by the sol-gel method, and its structural, morphological, magnetic, and magnetocaloric effects were investigated. The structural properties were analyzed by x-ray diffraction (XRD), and scanning electron microscopy (SEM) was used to characterize the morphology. An integrated magnetic measurement system was used to determine the magnetic properties. La 0.63 Sr 0.2 Nd 0.17 MnO 3 crystallized in a hexagonal crystal system with space group R -3 c . This was also confirmed by Rietveld refinement of the x-ray data from La 0.63 Sr 0.2 Nd 0.17 MnO 3 . With the doping of Nd 3+ , the cell volume decreases, which can be explained by the angles and bond lengths of the bonds between the Mn and O ions and the distortion of the lattice. Near the Curie temperature, La 0.63 Sr 0.2 Nd 0.17 MnO 3 exhibits significant magnetocaloric effects. The magnetic study of La 0.63 Sr 0.2 Nd 0.17 MnO 3 suggests that the transition from the paramagnetic to ferromagnetic phase can occur near the Curie temperature. The maximum magnetic entropy change and relative cooling power (RCP) of La 0.63 Sr 0.2 Nd 0.17 MnO 3 (298 K, 3 T) are 2.70 J/(kg K) and 135 (J/kg), respectively. The effect of f -orbitals on the magnetic properties of La 0.8 Sr 0.2 MnO 3 was investigated by first-principles calculations in density functional theory. Thus, it can be concluded that the magnetocaloric effects of the material after doping with f -orbital ions (Nd 3+ ) is enhanced compared to La 0.8 Sr 0.2 MnO 3 .