Ren Qingyong, Qi Ji, Yu Dehong, Zhang Zhe, Song Ruiqi, Song Wenli, Yuan Bao, Wang Tianhao, Ren Weijun, Zhang Zhidong, Tong Xin, Li Bing
Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
Spallation Neutron Source Science Center, Dongguan, 523803, China.
Nat Commun. 2022 Apr 28;13(1):2293. doi: 10.1038/s41467-022-29997-9.
One of the greatest obstacles to the real application of solid-state refrigeration is the huge driving fields. Here, we report a giant barocaloric effect in inorganic NHI with reversible entropy changes of [Formula: see text] ∼71 J K kg around room temperature, associated with a structural phase transition. The phase transition temperature, T, varies dramatically with pressure at a rate of dT/dP ∼0.79 K MPa, which leads to a very small saturation driving pressure of ΔP ∼40 MPa, an extremely large barocaloric strength of [Formula: see text] ∼1.78 J K kg MPa, as well as a broad temperature span of ∼41 K under 80 MPa. Comprehensive characterizations of the crystal structures and atomic dynamics by neutron scattering reveal that a strong reorientation-vibration coupling is responsible for the large pressure sensitivity of T. This work is expected to advance the practical application of barocaloric refrigeration.
固态制冷实际应用的最大障碍之一是巨大的驱动场。在此，我们报道了无机NHI中巨大的压热效应，在室温附近具有约71 J K⁻¹ kg⁻¹的可逆熵变，这与一个结构相变相关。相变温度T随压力急剧变化，变化率为dT/dP ∼0.79 K MPa⁻¹，这导致非常小的饱和驱动压力ΔP ∼40 MPa、极大的压热强度约1.78 J K⁻¹ kg⁻¹ MPa⁻¹以及在80 MPa下约41 K的宽温度跨度。通过中子散射对晶体结构和原子动力学进行的综合表征表明，强烈的重取向 - 振动耦合是T对压力高度敏感的原因。这项工作有望推动压热制冷的实际应用。
