Magnetic properties and giant reversible magnetocaloric effect in GdCoC2

Abstract

The crystal structure, magnetic properties and magnetocaloric effect (MCE) of GdCoC₂ have been studied. The compound crystallizes in an orthorhombic CeNiC₂-type structure which belongs to the Amm2 space group. A giant reversible MCE is observed in GdCoC₂ accompanied by a second-order paramagnetic to ferromagnetic (PM–FM) phase transition around the Curie temperature ∼15 K. For the magnetic field change of 0–5 T, the maximum values of the magnetic entropy change (−ΔS^max_M), relative cooling power (RCP), and refrigerant capacity (RC) are 28.4 J kg⁻¹ K⁻¹, 566 J kg⁻¹ and 369 J kg⁻¹, respectively. The present results indicate that GdCoC₂ is a promising candidate for low temperature magnetic refrigeration.