Magnetic properties of La0.65Ca0.30Pb0.05Mn0.9B0.1O3 (B = Co, Ni, Cu and Zn)

Abstract

The La0.65Ca0.30Pb0.05Mn0.9B0.1O3 (A = Co, Ni, Cu and Zn) manganites have been prepared via sol-gel method and sintered at 1100 degrees C for 24 h. The aim of the study was to investigate B-site cation doping effects on the magnetic properties. XRD analysis reveals that all samples have rhombohedral structure belonging to the R (3) over barc space group. The Curie temperature decreases as a result of Mn replacement with Co, Ni, Cu and Zn, respectively. The maximum magnetic entropy changes of the samples doped with Co, Ni, Cu and Zn for a field change of 1 T were found to be 2.10, 1.71, 3.20 and 1.42 J/kg K respectively. For La0.65Ca0.30Pb0.05MnO3, this is 2.60 J/kg K. The maximum magnetic entropy change increases as a result of Cu doping. Additionally, the metal-insulator transition temperature decreases due to the B-site doping. (C) 2014 Elsevier B.V. All rights reserved.