Abstract
Multicomponent perovskite nanomaterials Nd0.7Ca0.3Mn1-xNixO3 are synthesized and labeled as NMO, NCMO, NCMNO1, NCMNO2 and NCMNO3. Structural, magnetic and magnetocaloric properties have been investigated. X-ray diffraction analysis using Rietveld refinements confirm the formation of NdMnO3 nanocrystalline ortho-rhombic phase (Pnma) with the appearance of a secondary cubic phase Nd2O3 as justified by Hume-Rothery rule. The substitution of ions (Nd/Ca and Mn/Ni) alters the crystallite size, microstrain and the percentage of Nd2O3 phase. The replacement of Mn ions by Ni2+reduces the magnetization and changes the Curie temperature (Tc). The magnetocaloric effect has also been assessed by means of magnetic-entropy change, which is determined from field dependence of magnetization. It is found that a large magnetic-entropy change takes place around Tcfor the studied nanocomposites. Under an applied field interval of 100 kOe, the maximum magnetic-entropy changes -ASM = 2.07, 1.88 J/kg.K at AH = 7T occurs for NCMNO1 and NCMNO3, respectively.