Enhanced magnetocaloric properties with a tunable Curie temperature in (1 − x)La_{0.55 □ 0.1}Ca_0.35MnO₃/xLa_0.7Ca_0.2Sr_0.1MnO₃ system (0 ≤ x ≤ 1)

Improvement of magnetocaloric properties with tunable Curie temperature near room temperature is revealed to be possible by the mixture of both individual phases La_{0.55 □ 0.1}Ca_0.35MnO₃ (phase 1) and La_0.7Ca_0.2Sr_0.1MnO₃ (phase 2). This work demonstrates the outstanding agreement between the experimental results and the continuous curves predicted by numerical calculations in a two phases composite system (1 − x)La_{0.55 □ 0.1}Ca_0.35MnO₃/xLa_0.7Ca_0.2Sr_0.1MnO₃ (0 ≤ x ≤ 1). Our samples were synthesized using the sol–gel process and the solid-state reaction for phase 1 and phase 2, respectively. For both samples, a clear ferromagnetic (FM)-paramagnetic (PM) transition at the Curie temperature (T_C) is observed. Such a T_C is found to be 274.7 and 308 K for La_{0.55 □ 0.1}Ca_0.35MnO₃ and La_0.7Ca_0.2Sr_0.1MnO₃, respectively. Besides, the magnetic entropy change and the Relative Cooling Power (RCP) values were estimated for the biphasic system (1 − x)La_{0.55 □ 0.1}Ca_0.35MnO₃/xLa_0.7Ca_0.2Sr_0.1MnO₃ with 0 ≤ x ≤ 1. We revealed that the optimum magnetocaloric effect at µ₀H = 2 T has been found for the composition with x = 0.65, which displays a table-like ΔS curve with a peak value slightly lowered and strongly expanded around room temperature when compared with those of the parent compounds. Therefore, the obtained results will draw considerable attention in the field of research regarding the development of magnetic refrigeration devices.