物理学报2025，Vol.74Issue(13)：404-414,11.DOI:10.7498/aps.74.20250256
含重稀土元素的(Ln0.2La0.2Nd0.2Sm0.2Eu0.2)MnO3(Ln=Dy,Ho,Er)高熵钙钛矿陶瓷的制备及磁学性能
Preparation and magnetic properties of(Ln0.2La0.2Nd0.2Sm0.2Eu0.2)MnO3(Ln=Dy,Ho,Er)high-entropy perovskite ceramics containing heavy rare earth elements
摘要
Abstract
Equimolar ratio high-entropy perovskite ceramics(HEPCs)have attracted much attention due to their excellent magnetization intensity.To further enhance their magnetization intensities,(Ln0.2La0.2Nd0.2Sm0.2 Eu0.2)MnO3(Ln=Dy,Ho and Er,labeled as Ln-LNSEMO)HEPCs are designed based on the configuration entropy Sconfig,tolerance factor t,and mismatch degree σ2.Single-phase HEPCs are synthesized by the solid-phase method in this work,in which the effects of the heavy rare-earth elements Dy,Ho and Er on the structure and magnetic properties of Ln-LNSEMO are systematically studied.The results show that all Ln-LNSEMO HEPCs exhibit high crystallinity and maintain excellent structural stability after sintering at 1250 ℃for 16 h.Ln-LNSEMO HEPCs exhibit significant lattice distortion effects,with smooth surface morphology,clearly distinguishable grain boundaries,and irregular polygonal shapes.In the present work,the influences of A-site average ion radius,grain size and lattice distortion on the magnetic interactions of Ln-LNSEMO HEPCs are investigated.The three high-entropy ceramic samples exhibit hysteresis behavior at T=5 K,with the Curie temperature TC decreasing as the radius of the introduced rare-earth ions decreases,while the saturation magnetization and coercivity increase accordingly.When the average ionic radius of A-site decreases,the interaction between their valence electrons and local electrons in the crystal increases,thereby enhancing the conversion of electrons to oriented magnetic moments under an external magnetic field.Thus,Er-LNSEMO HEPC shows a higher saturation magnetization strength(42.8 emu/g)and coercivity(2.09 kOe)than the other samples,which is attributed to the strong magnetic crystal anisotropy,larger lattice distortion σ2(6.52×10-3),smaller average grain size(440.49±22.02 nm),unit cell volume(229.432 Å3)and A-site average ion radius(1.24 Å)of its magnet.The Er-LNSEMO HEPC has potential applications in magnetic recording materials.关键词
高熵陶瓷/稀土/钙钛矿/磁性能Key words
high-entropy ceramics/rare-earths/perovskite/magnetic properties引用本文复制引用
覃洁冬,冯兴民,文志勤,唐立,龙德凤,赵宇宏..含重稀土元素的(Ln0.2La0.2Nd0.2Sm0.2Eu0.2)MnO3(Ln=Dy,Ho,Er)高熵钙钛矿陶瓷的制备及磁学性能[J].物理学报,2025,74(13):404-414,11.基金项目
广西自然科学基金(批准号:2024GXNSFAA010415)和广西科技计划(批准号:桂科AD25069100)资助的课题. Project supported by the Natural Science Foundation of Guangxi Province,China(Grant No.2024GXNSFAA010415)and the Science and Technology Plan Project of Guangxi Province,China(Grant No.GuikeAD25069100). （批准号:2024GXNSFAA010415）
