Study of magnetocaloric properties of small Bi-doped Pr_0.55Ca_0.05Ba_0.40Mn_1−xBi_xO₃ manganites

Here, we investigated the magnetic and magnetocaloric (MC) properties of manganites labeled PrCaBaMnO and PrCaBaMnBiO, with compositions Pr_0.55Ca_0.05Ba_0.40Mn_1−xBi_xO₃ (x = 0 and 0.02), respectively. The solid-state reaction method was used for sample preparation, and the structural properties were checked using X-ray diffraction (XRD). Temperature dependence of magnetization (M(T)) measurements was carried out in the range of 5–300 K under 100 Oe field to determine the transition temperature of the manganites. Magnetic entropy change ( \(-\Delta {S}_{\text{M}}\) $-\mathrm{\Delta }{S}_{\text{M}}$ ) values were computed from field-dependent magnetization (M(H)) measurements. For the 2 T magnetic field values, the \(-\Delta {{S}_{ }}_{\text{M}}^{\text{max}}\) $-\mathrm{\Delta }S_{}^{}_{\text{M}}^{\text{max}}$ values for the PrCaBaMnO and PrCaBaMnBiO manganites are 3.15 and 2.86 Jkg^-1K^-1, respectively. Relative Cooling Power (RCP) values were calculated from the temperature dependence of \(-\Delta {S}_{\text{M}}\) $-\mathrm{\Delta }{S}_{\text{M}}$ (T) curves, resulting in 82.4 and 88.6 Jkg^-1 for PrCaBaMnO and PrCaBaMnBiO, respectively. Banerjee’s criterion and Franco’s universal master curve confirmed that the transition type for the studied manganites is second order.