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Title: Magnetic and magnetocaloric properties of iron subs tituted holmium chromite and dysprosium chromite

In this work, structural, magnetic, and magnetocaloric properties of HoCrO 3 and Fe substituted HoCrO 3 and DyCrO 3 (i.e. HoCr 0.7Fe 0.3O 3 and DyCr 0.7Fe 0.3O 3) powder samples were synthesized via a solution route. The structural properties of the samples were examined by Raman spectroscopy and x-ray diffraction techniques, which were further confirmed using first-principle calculations. The dc magnetic measurements indicate that the Cr 3+ ordering temperatures for the HoCrO 3, HoCr 0.7Fe 0.3O 3, and DyCr 0.7Fe 0.3O 3 samples are 140 K, 174 K, and 160 K, respectively. The ac magnetic measurements not only confirmed the Cr 3+ ordering transitions in these samples (obtained using dc magnetic measurements), but also clearly showed the Ho 3+ ordering at ~10 K in the present HoCrO 3 and HoCr 0.7Fe 0.3O 3 samples, which to our knowledge, is the first ac magnetic evidence of Ho 3+ ordering in this system. The effective magnetic moments were determined to be 11.67μB, 11.30μB, and 11.27μB for the HoCrO 3, HoCr 0.7Fe 0.3O 3, and DyCr 0.7Fe 0.3O 3 samples, respectively. For the first time, the magnetocaloric properties of HoCrO 3 and HoCr 0.7Fe 0.3O 3 were studied here, showing their potentialmore » for applications in magnetic refrigeration. In an applied dc magnetic field of 7 T, the maximum magnetocaloric value were determined to be 7.2 (at 20 K), 6.83 (at 20 K), 13.08 J/kg K (at 5 K) and the relative cooling power were 408, 387, and 500 J/kg for the HoCrO 3, HoCr 0.7Fe 0.3O 3, and DyCr 0.7Fe 0.3O 3 samples, respectively.« less
Authors:
 [1] ;  [2] ;  [1] ;  [2] ;  [1]
  1. Univ. of Connecticut, Storrs, CT (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
OSTI Identifier:
1324067
Grant/Contract Number:
AC05-00OR22725
Type:
Accepted Manuscript
Journal Name:
RSC Advances
Additional Journal Information:
Journal Volume: 6; Journal Issue: 12; Journal ID: ISSN 2046-2069
Publisher:
Royal Society of Chemistry
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Oak Ridge Leadership Computing Facility (OLCF)
Sponsoring Org:
USDOE Office of Science (SC)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE