Large magnetocaloric effect in a ternary Laves phase compoundHo2Rh3Ge

Structural and magnetic properties of an intermetallic Ho ₂Rh ₃ Ge compound have been investigated in this paper. We report the observation of large magnetocaloric effect (MCE) in Ho ₂Rh ₃ Ge from the characterization of magnetism isotherms. The Rietveld refinement of powder X-ray diffraction revealed that Ho ₂Rh ₃ Ge crystallizes in a rhombohedral Laves phase structure (space group R 3 ̄ m , hR18). It exhibits ferromagnetic order below the Curie temperature T _C = 13 K. Around T _C, maximum value of entropy change −Δ S _m = 25.4 J kg ⁻¹ K ⁻¹ was observed for a change of magnetic field 0−8 T. The obtained refrigeration capacity (relative cooling power) for a change of magnetic field from 0 8 T is 497(664) J.kg ⁻¹. The second –order magnetic phase transition in Ho ₂Rh ₃Ge is confirmed from Arrott plots, universal scaling plots of magnetic entropy changes, and also from the field dependence of the magnetic entropy change.