Magnetic effect and chemical distribution study of LCMNO3 perovskite by photoelectron spectroscopy

Abstract The crystal structure, x-ray photoemission spectroscopy, magnetic characteristics, and magnetocaloric performance of perovskite La 0.55 Ca 0.45 Mn 0.8 Nb 0.2 O 3 (LCMNO) ceramic powder were analyzed. The orthorhombic structure with a Pnma space group was found as the main phase in the as-received compound after the XRD pattern refinement. The mixed-valence states of manganese were detected by x-ray photoemission spectroscopy (XPS). The analysis of the La3d line revealed the complex nature of the lanthanum states. The evaluation of Zero-Field-Cooled and Field-Cooled magnetization performance provided conclusive evidence for the existence of the antiferromagnetic Mn 3 O 4 phase at a temperature of T N = 42 K and the coexistence of CO- AFM and FM domains in LCMNO. Despite the observed significant ( δ T FWHM ) value due to relatively low magnetic entropy change (ΔS M ), the relative cooling power (RCP) is relatively moderate. By adding Nb 4+ , the changes in Mn valences and their effect on the magnetic cooling effect are lessened.