The Magnetic and Magnetocaloric Properties of Pr1−xBixMnO3 (x = 0.2 and 0.4) Manganites

The magnetic and magnetocaloric properties of Pr1−xBixMnO3 (x = 0.2 and 0.4) nanocrystalline manganites have been studied systematically. Samples were prepared using the Pechini sol–gel method. The variation of the magnetization as a function of temperature and applied magnetic field were carried out. Magnetic measurements show that all the materials exhibit a paramagnetic–ferromagnetic transition when the temperature decreases. Magnetocaloric effect has been calculated in terms of isothermal magnetic entropy change. A large magnetocaloric effect has been observed, the maximum entropy change, ΔSMmax\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}${\Delta S}_{\mathrm {M}}^{\text {max}}$\end{document}¦reaches 0.7 and 2.1 J kg−1 K−1 under a magnetic applied field of 5 T with an RCP values of 183 J kg−1 for Pr0.8Bi0.2MnO3 sample. These perovskites have the large magnetic entropy changes induced by low magnetic field change, which is beneficial for the household application of active magnetic refrigerant (AMR) materials.