Magnetocaloric effect of mononitride containing gadolinium and dysprosium GdxDy1-xN

The binary rare-earth mononitride, GdxDy1-xN, was synthesized by carbothermic reduction performed in a nitrogen gas stream. A continuous solid solution with the NaCl structure was observed through the whole composition range, and the Curie temperature was found to vary from 61 to 21 K as x changes from I to 0. The magnetocaloric effect was evaluated as a function of x by calculating the magnetic entropy changes DeltaS from the magnetization data sets measured at various temperatures and applied fields. The DeltaS values of GdxDy1-xN expressed in terms of J K-1 m(-3) were comparable to those of intermetallic compounds of rare earth and transition metals previously reported. GdxDy1-xN is a promising magnetic refrigerant for hydrogen liquefying system because rare earth nitrides would not react with hydrogen. (C) 2003 Elsevier B.V. All rights reserved.