Large reversible magnetocaloric effect in ferromagnetic semiconductor EuS

We present the large reversible magnetocaloric effect (MCE) of the ferromagnetic semiconductor EuS, which shows a maximum magnetic entropy change of -Delta S-m(max) similar to 37 J kg(-1) K-1, an adiabatic temperature change of Delta T-ad similar to 10.4 K and a relative cooling power of RCP similar to 782 J kg(-1) at 18.5 K for a magnetic field change Delta H = 5 T. Particularly, the large MCE is isotropic and without hysteresis loss, even for a magnetic field change of 2 T the values of -Delta S-m(max), Delta T-ad and RCP reach as high as 22 J kg(-1) K-1, 7.5 K and 284 J kg(-1), respectively. These results indicate that EuS has excellent refrigeration performance at the temperatures near 20 K, and thus can be considered as the potential magnetic refrigerant material for liquefaction of hydrogen. (C) 2014 Elsevier Ltd. All rights reserved.