Giant barocaloric effect in hexagonal Ni2In-type Mn-Co-Ge-In compounds around room temperature

• DOI: 10.1038/srep18027
• Publication Date: 2015-12-17T11:52:04Z
• Authors: Rong-Rong Wu; Li-Fu Bao; Feng-Xia Hu; Hui Wu; Qing-Zhen Huang; Jing Wang; Xiao-Li Dong; Guan-Nan Li; Ji-Rong Sun; Fei-Ran Shen; Tong-Yun Zhao; Xin-Qi Zheng; Li-Chen Wang; Yao Liu; Wen-Liang Zuo; Ying-Ying Zhao; Ming Zhang; Xian-Cheng Wang; Chang-Qing Jin; Guang-Hui Rao; Xiu-Feng Han; Bao-Gen Shen
• Keywords: Magnetic refrigeration; Ambient pressure; Hydrostatic pressure; Hydrostatic equilibrium

Abstract The most widespread cooling techniques based on gas compression/expansion encounter environmental problems. Thus, tremendous effort has been dedicated to develop alternative technique and search for solid state materials that show large caloric effects. An application of pressure a material can cause change in temperature, which is called the barocaloric effect. Here we report giant effect hexagonal Ni 2 In-type MnCoGe 0.99 In 0.01 compound involving magnetostructural transformation, T mstr , accompanied with big difference internal energy due great negative lattice expansion( ΔV/V ~ 3.9%). High resolution neutron diffraction experiments reveal hydrostatic push lower temperature at rate 7.7 K/kbar, resulting entropy under moderate 3 kbar reaches 52 Jkg −1 K exceeds materials, including reported magnetocaloric driven by 5 magnetic field available only superconducting magnets.