Large Barocaloric Effect with High Pressure-Driving Efficiency in a Hexagonal MnNi0.77Fe0.23Ge Alloy

Qingqi Zeng, Jianlei Shen, Enke Liu, Xuekui Xi, Wenhong Wang, Guangheng Wu, Xixiang Zhang

Research output: Contribution to journalArticlepeer-review

Abstract

The hydrostatic pressure is expected to be an effective knob to tune the magnetostructural phase transitions of hexagonal MM'X alloys (M and M' denote transition metals and X represents main group elements). We perform magnetization measurements under hydrostatic pressure on an MM'X martensitic MnNi20.77Fe0.23Ge alloy. The magnetostructural transition temperature can be efficiently tuned to lower temperatures by applying moderate pressures, with a giant shift rate of -151 K/GPa. A temperature span of 30 K is obtained under the pressure, within which a large magnetic entropy change of -23 J⋅kg-1K-1 in a field change of 5 T is induced by the mechanical energy gain due to the large volume change. Meanwhile, a decoupling of structural and magnetic transitions is observed at low temperatures when the martensitic transition temperature is lower than the Curie temperature. These results show a multi-parameter tunable caloric effect that benefits the solid-state cooling.
Original languageEnglish (US)
Pages (from-to)076101
JournalChinese Physics Letters
Volume37
Issue number7
DOIs
StatePublished - Jul 14 2020

Fingerprint Dive into the research topics of 'Large Barocaloric Effect with High Pressure-Driving Efficiency in a Hexagonal MnNi0.77Fe0.23Ge Alloy'. Together they form a unique fingerprint.

Cite this