Exceptional Cooling Capacity of LiGd<sub>0.1</sub>Yb<sub>0.9</sub>F<sub>4</sub> at Sub‐Kelvin Temperatures
Abstract
AbstractAdiabatic demagnetization refrigeration, which utilizes the magnetocaloric effect of magnetic refrigerants, stands as the sole cooling technology capable of achieving sub‐Kelvin temperatures efficiently and reliably without relying on scarce 3He resources or gravity. However, current sub‐Kelvin magnetic refrigerants encounter challenges such as structural instability in vacuum or under mild heating, along with small magnetic entropy change (−ΔSm) values, which significantly limit their practical applications. Here a water‐free magnetic refrigerant, LiGd0.1Yb0.9F4 is reported, prepared by introducing Li⁺ ions to reduce the dipolar interactions between Gd3+ ions and/or Yb3+ ions. Notably, this refrigerant possesses a magnetic ordering temperature of 85 mK, while its experimental −ΔSm reaches up to 136 mJ cm−3 K−1 (0.68 K and 2 T), more than three times the theoretical value of CrK(SO4)2·12H2O. Significantly, this refrigerant not only cools the test sample to temperatures as low as 160 mK but also achieves a specific cooling capacity of 46.943 mJ cm−3 T−1 at 300 mK. Remarkably, the specific cooling capacity at 300 mK is more than double that of commercial CrK(SO4)2·12H2O, representing one of the most notable values reported among all known magnetic refrigerants operating at sub‐Kelvin temperatures.
Article Details
Authors (7)
Qiao‐Fei Xu
Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China
Peng Zhao
Man‐Ting Chen
Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China
Ruo‐Tong Wu
Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China
Wei Dai
Université Paris Cité, Institut de Physique du Globe de Paris, CNRS
La‐Sheng Long
State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen China
Lan‐Sun Zheng
State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen China