Magnetic and Table-Like Magnetocaloric Properties of Polycrystalline Pr0.7Ba0.1Sr0.2MnO3

Abstract

The magnetic and magnetocaloric properties of Pr0.7Ba0.1Sr0.2MnO3 polycrystalline are presented. The sample is single phase of a monoclinic structure with a = 5.4726 A, b = 5.5045 A, c = 7.7339 A, α = γ = 90°, and β = 90.003°. X-ray absorption spectrum shows a co-existence of Mn4+ and Mn3+ ions in the compound. A ferromagnetic–paramagnetic (FM–PM) phase transition occurs at around 232 K. An analysis of the critical behavior near the FM–PM transition indicates a short-range magnetic ordering in Pr0.7Ba0.1Sr0.2MnO3 with critical exponents dependent on an applied magnetic field. The critical parameters are found to be β = 0.220 ± 0.03, 0.224 ± 0.002, and 0.227 ± 0.002, γ = 0.732 ± 0.011, 0.818 ± 0.003, and 0.958 ± 0.013, TC = 232.7, 234.6, and 236.6 K for field ranges of 1–3 T, 3–4 T and 4–5 T, respectively. The maximum entropy change (− ΔSmax) is found to be 5.67 J/kg K near the TC for a 5 T of field change. The table-like magnetocaloric effect observed in this sample is desirable for active magnetic refrigeration.