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This content will become publicly available on January 11, 2017

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

In this work, structural, magnetic, and magnetocaloric properties of HoCrO3 and Fe substituted HoCrO3 and DyCrO3 (i.e. HoCr0.7Fe0.3O3 and DyCr0.7Fe0.3O3) 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 Cr3+ ordering temperatures for the HoCrO3, HoCr0.7Fe0.3O3, and DyCr0.7Fe0.3O3 samples are 140 K, 174 K, and 160 K, respectively. The ac magnetic measurements not only confirmed the Cr3+ ordering transitions in these samples (obtained using dc magnetic measurements), but also clearly showed the Ho3+ ordering at ~10 K in the present HoCrO3 and HoCr0.7Fe0.3O3 samples, which to our knowledge, is the first ac magnetic evidence of Ho3+ ordering in this system. The effective magnetic moments were determined to be 11.67μB, 11.30μB, and 11.27μB for the HoCrO3, HoCr0.7Fe0.3O3, and DyCr0.7Fe0.3O3 samples, respectively. For the first time, the magnetocaloric properties of HoCrO3 and HoCr0.7Fe0.3O3 were studied here, showing their potential 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 5more » K) and the relative cooling power were 408, 387, and 500 J/kg for the HoCrO3, HoCr0.7Fe0.3O3, and DyCr0.7Fe0.3O3 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 Laboratory (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