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Single-phase high-entropy perovskite ceramics (Ln 0.2 Gd 0.2 La 0.2 Nd 0.2 Sm 0.2)MnO 3 (Ln-GLNSMO HEPCs) have been synthesized using solid-state reactions. The effect of A-site rare-earth ions (Ln = Eu, Ho, Yb) on the structure and magnetic properties was systematically investigated. The results show that all samples are orthorhombic phases (with a space group of Pbnm) and exhibit a strong crystallization trend sintered at 1300 °C for 16 h. All the HEPCs are composed of irregular spherical particles with smooth surfaces and show obvious hysteresis effects at T = 5 K. The changing Mn–O bond distance, Mn–O–Mn bond angle and the increase of Mn4+ ion concentration enhance the double exchange effect of Mn3+-O2--Mn4+, leading to different magnetic interactions. The residual magnetization M r (coercivity H c) of the samples is significantly enhanced, which is increasing from 0.13 emu/g (16.34 Oe) to 3.17 emu/g (97.07 Oe) due to the increase of configuration entropy, lattice distortion and the double exchange effect (DE). In addition, there is a strong relationship between the magnetic properties and the average radius of the A-site ions, in which Ho-GLNSMO HEPCs have a high M s magnetism. This work is a valuable reference for the magnetic regulation of high-entropy ceramics based on rare-earth and entropy-stabilized perovskite types. [ABSTRACT FROM AUTHOR]

• GLNSYMnO 3 has a single-phase orthorhombic perovskite structure sintered at 1250 °C. • The high configurational entropy drives the structural stability of GLNSYMnO 3 even at temperatures below T C. • GLNSYMnO 3 has good magnetism due to the lattice distortion and double-exchange. • GLNSYMnO 3 is a second-order magnetic phase transition material with potential applications in magnetic storage. Rare-earth transition element high-entropy perovskite ceramics (HEPCs) (Gd 0.2 La 0.2 Nd 0.2 Sm 0.2 Y 0.2)MnO 3 (GLNSYMnO 3) were prepared by using a solid-state reaction method, and the structure, morphology and magnetic properties of the GLNSYMnO 3 were studied. The crystalline structure of GLNSYMnO 3 is a smooth surface and similar to "cashews" tubular particles, and a single-phase orthorhombic (Pbnm Space group) perovskite without impurities is confirmed when the sintered temperature reaches or exceeds 1250 °C by the analysis of phase composition and microstructures. Magnetic measurements indicate that GLNSYMnO 3 HEPCs have low Curie temperature (T C = 61 K), but they exhibit a good magnetism by comparison with other high-entropy ceramics, which is caused by the lattice distortion and exchange interactions between high concentrations of Mn3+ (92.4 %) and non-magnetic oxygen ions, promoting the movement of circulating electrons. GLNSYMnO 3 HEPCs did not undergo a phase transition below T C due to high configurational entropy driving structural stability. In addition, GLNSYMnO 3 HEPCs undergo a second-order magnetic phase transition from isothermal magnetization curves and Arrot curves, which have potential applications in magnetic storage. [ABSTRACT FROM AUTHOR]