Structural, magnetic, and cryogenic magnetocaloric properties in the quaternary rare earths (RE) based RECr2Si2C (RE = Gd, Tb, Dy) compounds

The rare earths (RE) based materials with large reversible magnetocaloric effects have been recently recognized as good candidates for practical cryogenic magnetic refrigeration. In this work, three RE-based quaternary silicon carbides of RECr2Si2C (RE = Gd, Tb, Dy) were synthesized and determined the crystal structure, magnetic properties, magnetic phase transition, and magnetocaloric performances. All RECr2Si2C compounds are crystallized in the carbon-filled CeMg2Si2-type crystal structure and revealed a secondorder magnetic phase transition from ferromagnetic to paramagnetic without noticeable field or thermal hysteresis around the Curie temperatures (similar to 10.9 K for GdCr2Si2C, similar to 16.6 K for TbCr2Si2C, and similar to 10.7 K for DyCr2Si2C). The magnetocaloric parameters including the maximum magnetic entropy change, temperature-averaged entropy changes with 3 K lift, as well as refrigerant capacity/relative cooling power are applied to determine the magnetocaloric performances, and the evaluated values are 21.7, 14.6 and 9.8 J/kgK, 20.97, 14.51, and 9.73 J/kgK, as well as 248.3/328.8, 302.8/393.8, and 211.3/274.9 J/kg for GdCr2Si2C, TbCr2Si2C, and DyCr2Si2C under the field change of 0-50 kOe. These results indicate that the GdCr2Si2C possesses promising magnetocaloric performances and is considerable for cryogenic magnetic refrigeration application. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

In this study, three rare earth-based quaternary silicon carbides were synthesized and characterized for their crystal structure, magnetic properties, magnetic phase transition, and magnetocaloric performances. Among them, GdCr2Si2C showed promising magnetocaloric performances for cryogenic magnetic refrigeration applications.