Magnetic and magnetocaloric properties of selected Pb-doped manganites

In this paper, we report the effect of Pb doping on the magnetic and magnetocaloric properties of La_0.7Ca_0.3-x Pb _x MnO₃ (0.15 ≤ x ≤ 0.3) polycrystalline samples. The samples were prepared by solid state synthesis method. X-ray diffraction patterns indicate that these samples have monoclinic structure with the Pc/2 space group. The magnetization measurements indicated that all samples exhibited a paramagnetic–ferromagnetic transition and the transition temperature increased with increasing of Pb concentration. Using phenomenological model, the magnetocaloric behavior of all the samples has been calculated based on the experimental magnetization data. Our results on the magnetocaloric properties suggest that the compound La_0.7Ca_0.15Pb_0.15MnO₃ is attractive as a possible material for magnetic refrigeration.