Changes in La_0.8Sr_0.2MnO₃ manganites structure, magnetic and magnetocaloric properties by Pr³⁺ doping

With the growing attention to perovskite materials in the field of magnetic refrigeration. In this work, La_0.8−xPr_xSr_0.2MnO₃ (x = 0.05, 0.10, 0.15) (LPSMO) samples were synthesized through the sol–gel method. The effects of Pr³⁺ doping on the structure, morphology, and magnetization of LPSMO were investigated. The XRD analysis revealed that the LPSMO samples have a rhombohedral structure within the R-3c space group. As the amount of Pr³⁺ doping increased, the cell volume decreased. The magnetic properties of LPSMO exhibited a transition from ferromagnetic (FM) to paramagnetic (PM) near the Curie temperature (Tc), with Tc decreasing as the Pr³⁺ doping level increased. The second-order magnetic phase transition of LPSMO near Tc was confirmed by employing the MPMS. The maximum magnetic entropy change ( \(-\Delta {S}_{M}^{max}\) $-\mathrm{\Delta }{S}_M^{\mathit{max}}$ ) of LPSMO is 4.92 J/(kg·K) (x = 0.05), 5.13 J/(kg·K) (x = 0.10) and 5.04 J/(kg·K) (x = 0.15) when the external magnetic field (H) = 5 T, separately. Meanwhile, the relative cooling power (RCP) of LPSMO are 283.88, 276.71, and 289.60 J·kg⁻¹, respectively. The experiments indicate that LPSMO has promising application prospects.