Low-temperature magnetic properties and large magnetocaloric effects in the RE3Rh2 (RE = Nd, Ho and Er) intermetallics

The cryogenic magnetic properties and magnetocaloric effects of Er3Ni2-type Nd3Rh2 (space group R-3, N148, hR45), and Y3Rh2-type RE3Rh2 (RE = Ho, Er) (space group I4/mcm, N140, tI140) have been investigated in detail. For the Nd3Rh2 compound, two second-order magnetic transitions, a ferromagnetic-antiferromagnetic transition followed by an antiferromagnetic-paramagnetic transition with temperature increasing, are observed at Tt = 13 K and TN = 17 K, respectively. For the RE3Rh2 (RE = Ho, Er) compounds, it exhibits a ferromagnetic ordering around the Curie temperature 23 K and 8 K, respectively. The reciprocal magnetic susceptibility of RE3Rh2 (RE = Ho, Er) obey the Curie-Weiss law in the paramagnetic region, the values of the effective magnetic moment are determined to be 10.30 μB/Ho3+ and 10.62 μB/Er3+, and the corresponding paramagnetic Curie temperatures are 13 K and 4.5 K, respectively. The maximum values of magnetic entropy changes for RE3Rh2 (RE = Nd, Ho and Er) are achieved to be 3.78 J/kg K, 14.01 J/kg K and 20.01 J/kg K with an effect refrigerant capacity values of 68 J/kg, 382 J/kg and 267 J/kg for a field change of 0–5 T, respectively. Large magnetocaloric effects indicate the potentiality of the RE3Rh2 (RE = Nd, Ho and Er) compounds as candidates in low temperature magnetic refrigerant.