Prediction of magnetocaloric effect in La0.8Sr Ca0.2−MnO3 compounds (x = 0.05, 0.1 and 0.15) with a first-order magnetic phase transition

Na-doped La 0.7 Ca 0.3 MnO 3 compounds exhibiting a large magnetocaloric effect near room temperature

“…Under 12 kOe, the maximum and minimum values of ΔC P (T,H) calculated to be about ± 145, ± 20, and ± 12 J kg −1 K −1 for samples x=0, 0.05, and 0.1, respectively. These results are higher than those reported for some A-doped LCMO exhibiting MCE at near RT [9,16].…”

“…For 12 kOe, the value of ΔT max is found to be about 2.5, 1.0, and 0.8 K that takes place at T=259, 288, and 300 K for x=0, 0.05, and 0.1, respectively. These values are significantly higher than those reported for some Adoped manganites if compared in the same field change [14,16]. However, in comparing with Gd metal [27], these values are modest, but with advanced features such as easy to prepare, controllable T C , high chemical stability, low-cost, wide magnetic phase transition region, and high RCP value, La 0.7−x Na x Ca 0.3 MnO 3 compounds should be considered as a potential candidate for the Ericsoncycle magnetic refrigerator near the RT region.…”

“…2(b) for a representative sample x=0.05. According to a phenomenological model that can be used to predict about the magnetocaloric properties for some manganites [9,14,16], M(T) data can be described by…”

“…Based on the phenomenological model, the change in the adiabatic temperature (ΔT) for the samples can be evaluated by using the equation [14,16]:…”

Magnetocaloric effect and critical behavior near the first to second-order phase transition of La0.7Ca0.3−xSnxMnO3 compounds

“…Due to different ion sizes occupy at A-site (La/Ca/Sn-site) in perovskite structure, there is a size disorder between the ions. This disorder created a strong local stress in MnO 6 octahedral and also varying the Mn-O-Mn angles leading to the change in structural parameters and magnetic characters [28,32]. Figure 3(b) shows M(T) curves for samples measured at H=10 kOe, where the solid lines are fitting curves of experimental data to a phenomenological model, which was suggested by Hamad [24,25].…”