Levinsky J J B, Beckmann B, Gottschall T, Koch D, Ahmadi M, Gutfleisch O, Blake G R
Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 3, 9747AG, Groningen, The Netherlands.
EaStCHEM School of Chemistry and Centre for Science at Extreme Conditions, University of Edinburgh, Joseph Black building, David Brewster Road, EH9 3FJ, Edinburgh, UK.
Nat Commun. 2024 Oct 3;15(1):8559. doi: 10.1038/s41467-024-52837-x.
Magnetic refrigeration, which utilizes the magnetocaloric effect, can provide a viable alternative to the ubiquitous vapor compression or Joule-Thompson expansion methods of refrigeration. For applications such as hydrogen gas liquefaction, the development of magnetocaloric materials that perform well in moderate magnetic fields without using rare-earth elements is highly desirable. Here we present a thorough investigation of the structural and magnetocaloric properties of a novel layered organic-inorganic hybrid coordination polymer Co(OH)(SO)[enH] (enH = ethylenediammonium). Heat capacity, magnetometry and direct adiabatic temperature change measurements using pulsed magnetic fields reveal a field-dependent ferromagnetic second-order phase transition at 10 K < < 15 K. Near the hydrogen liquefaction temperature and in a magnetic field change of 1 T, a large maximum value of the magnetic entropy change, = - 6.31 J kg K, and an adiabatic temperature change, = 1.98 K, are observed. These values are exceptional for rare-earth-free materials and competitive with many rare-earth-containing alloys that have been proposed for magnetic cooling around the hydrogen liquefaction range.
磁制冷利用磁热效应，可为普遍使用的蒸汽压缩制冷或焦耳 - 汤姆逊膨胀制冷方法提供可行的替代方案。对于诸如氢气液化等应用而言，开发在中等磁场中表现良好且不使用稀土元素的磁热材料是非常有必要的。在此，我们对一种新型层状有机 - 无机杂化配位聚合物Co(OH)(SO)[enH]（enH = 乙二铵）的结构和磁热性能进行了全面研究。利用脉冲磁场进行的热容量、磁测量和直接绝热温度变化测量表明，在10 K < < 15 K范围内存在场依赖的铁磁二级相变。在接近氢气液化温度且磁场变化为1 T时，观察到磁熵变的最大值 = - 6.31 J kg K，以及绝热温度变化 = 1.98 K。这些值对于无稀土材料来说是非常出色的，并且与许多已被提议用于氢气液化温度范围附近磁制冷的含稀土合金具有竞争力。
