Lin Junli, Feizpour Mahdi, Zhang Yikun, He Ningzhou, Feizpour Darja, Li Lingwei
Key Laboratory of Novel Materials for Sensor of Zhejiang Province & School of Electronics and Information, Hangzhou Dianzi University, Hangzhou 310012, China.
Department of Materials Science and Engineering, School of Engineering, Meybod University, Yazd 89616-99557, Iran.
ACS Appl Mater Interfaces. 2024 Sep 25;16(38):51163-51169. doi: 10.1021/acsami.4c12253. Epub 2024 Sep 11.
The magnetocaloric effect (MCE) is currently intensively investigated in various rare earths ()-containing magnetic solids, not only for developing appropriate magnetocaloric materials (MCMs) for cryogenic magnetic cooling but also for deepening our understanding into the inherent physical properties of these materials. Here, we provide a systematic experimental investigation into a series of new CuTiO ( = Dy, Ho, Er) double-perovskite (DP) oxides regarding the structural and magnetic properties, especially for their cryogenic MCE and magnetic-phase transition (MPT). All of these CuTiO oxides crystallize in a -site-ordered hexagonal DP-type structure with the symmetry of the crystallographic space group 6̅2. These DP oxides exhibit magnetic ordering, with MPT temperatures of approximately 2.7, 2.2, and 2.7 K for DyCuTiO, HoCuTiO, and ErCuTiO, respectively. The magnetocaloric performances of the CuTiO DP oxides were characterized by the peak values of magnetic entropy change, the temperature-averaged magnetic entropy change (5K-lift), and relative cooling powers. These magnetocaloric parameters were deduced to be 18.7/17.9 J/kgK and 298.2 J/kg for DyCuTiO, 12.5/12.2 J/kgK and 273.9 J/kg for HoCuTiO, and 13.8/12.9 J/kgK and 188.4 J/kg for ErCuTiO under a magnetic field change of 0-5 T. These values are comparable to those of most reported -containing magnetocaloric materials, indicating that these CuTiO DP oxides are promising candidates for cryogenic magnetic cooling applications.
目前，人们正在对各种含稀土（）的磁性固体中的磁热效应（MCE）进行深入研究，这不仅是为了开发适用于低温磁制冷的磁热材料（MCM），也是为了加深我们对这些材料固有物理性质的理解。在此，我们对一系列新型CuTiO（= Dy、Ho、Er）双钙钛矿（DP）氧化物的结构和磁性进行了系统的实验研究，特别是它们的低温MCE和磁相变（MPT）。所有这些CuTiO氧化物都结晶为具有晶体空间群6̅2对称性的A位有序六方DP型结构。这些DP氧化物表现出磁有序，DyCuTiO、HoCuTiO和ErCuTiO的MPT温度分别约为2.7、2.2和2.7 K。通过磁熵变的峰值、温度平均磁熵变（5K提升）和相对冷却功率来表征CuTiO DP氧化物的磁热性能。在0 - 5 T的磁场变化下，这些磁热参数推断为：DyCuTiO为18.7/17.9 J/kgK和298.2 J/kg，HoCuTiO为12.5/12.2 J/kgK和273.9 J/kg，ErCuTiO为13.8/12.9 J/kgK和188.4 J/kg。这些值与大多数报道的含磁热材料的值相当，表明这些CuTiO DP氧化物是低温磁制冷应用的有前途的候选材料。
