Effects of Eu3+ doping on the structural, magnetocaloric effect and critical behavior of Ruddlesden-Popper compounds La1.4-xEuxSr1.6Mn2O7 (0 ≤ x ≤ 0.1)

• Published in: Journal of alloys and compounds Vol. 1010
• Main Authors: Feng, Min, Xie, Zhuojia, Zou, Zhengguang, Jiang, Xinyu, Zheng, Xiuxin, Xu, Changji, Zhang, Weijian, Yu, Fagang, He, Wenbin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05-01-2025
• Subjects: Critical behavior; Magnetocaloric effect; Ruddlesden-Popper structure; Magnetocaloric effect; Ruddlesden-Popper structure; Critical behavior
• ISSN: 0925-8388
• DOI: 10.1016/j.jallcom.2024.177111

The effects of Eu3+ doping on the structural and magnetocaloric effect of Ruddlesden-Popper compounds La1.4-xEuxSr1.6Mn2O7 (0 ≤ x ≤ 0.1) were investigated. The X-ray diffraction and infrared spectroscopy confirmed that La1.4-xEuxSr1.6Mn2O7 compounds exhibited the tetragonal lattice symmetry (I4/mmm) of the Ruddlesden-Popper phase. The crystal structure of La1.4-xEuxSr1.6Mn2O7 compounds distorted and phase separated as the amount of Eu3+ doping varied. The magnetization-temperature curves demonstrated that La1.4-xEuxSr1.6Mn2O7 compounds display a notable transition temperature attributed to its anisotropic exchange coupling. The maximum magnetic entropy changes (−ΔSMmax) of La1.4-xEuxSr1.6Mn2O7(x = 0, 0.075, and 0.1) compounds are 2.82, 3.12 and 3.40 J/(kg·K) at the 5 T applied magnetic field. Meanwhile, its relative cooling power (RCP) was 186.37, 207.42 and 242.54 J/kg, respectively. The critical behavior of La1.4-xEuxSr1.6Mn2O7 (0≤x≤0.1) compounds was analyzed around Tc, and it was found that the critical index (β = 0.413, γ = 1.020, δ = 3.038) is essentially in line with the mean field theory.
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•The crystal structure of LESMO compounds distorted as the Eu3+ doping varied.•The −ΔSMmax of La1.3Eu0.1Sr1.6Mn2O7 compounds is 3.40 J/(kg K) as H = 5 T.•The RCP of La1.3Eu0.1Sr1.6Mn2O7 compounds is 242.54 J/kg when H = 5 T.•The critical behavior of LESMO compounds near Tc is consistent with the mean-field model.