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Title: Large scale growth and magnetic properties of Fe and Fe{sub 3}O{sub 4} nanowires

Abstract

Fe and Fe{sub 3}O{sub 4} nanowires have been synthesized by thermal decomposition of Fe(CO){sub 5}, followed by heat treatments. The Fe wires are formed through the aggregation of nanoparticles generated by decomposition of Fe(CO){sub 5}. A core-shell structure with an iron oxide shell and Fe core is observed for the as-prepared Fe wires. Annealing in air leads to the formation of Fe{sub 2}O{sub 3}/Fe{sub 3}O{sub 4} wires, which after heat treatment in a N{sub 2}/alcohol atmosphere form Fe{sub 3}O{sub 4} wires with a sharp Verwey [Nature (London) 144, 327 (1939)] transition at 125 K. The Fe{sub 3}O{sub 4} wires have coercivities of 261 and 735 Oe along the wire axis at RT and 5 K, respectively. The large increase of coercivity at 5 K as compared to RT is due to the increase of anisotropy resulting from the Verwey transition.

Authors:
; ; ; ; ; ;  [1];  [2];  [3];  [4];  [3]
  1. Graduate Center for Materials Research, University of Missouri-Rolla, Rolla, Missouri 65409 (United States)
  2. (Singapore)
  3. (United States)
  4. (China)
Publication Date:
OSTI Identifier:
20788148
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 99; Journal Issue: 8; Other Information: DOI: 10.1063/1.2172208; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AFTER-HEAT; AGGLOMERATION; AIR; ALCOHOLS; ANISOTROPY; ANNEALING; ATMOSPHERES; COERCIVE FORCE; CRYSTAL GROWTH; FERROMAGNETIC MATERIALS; IRON; IRON OXIDES; MAGNETIC PROPERTIES; PARTICLES; PYROLYSIS; QUANTUM WIRES; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0000-0013 K; TEMPERATURE RANGE 0065-0273 K

Citation Formats

Yang, J. B., Xu, H., You, S. X., Zhou, X. D., Wang, C. S., Yelon, W. B., James, W. J., Physics Department, National University of Singapore, Singapore 117542, Graduate Center for Materials Research, University of Missouri-Rolla, Rolla, Missouri 65409, School of Physics, Peking University, Beijing 100871, and Graduate Center for Materials Research, University of Missouri-Rolla, Rolla, Missouri 65409. Large scale growth and magnetic properties of Fe and Fe{sub 3}O{sub 4} nanowires. United States: N. p., 2006. Web. doi:10.1063/1.2172208.
Yang, J. B., Xu, H., You, S. X., Zhou, X. D., Wang, C. S., Yelon, W. B., James, W. J., Physics Department, National University of Singapore, Singapore 117542, Graduate Center for Materials Research, University of Missouri-Rolla, Rolla, Missouri 65409, School of Physics, Peking University, Beijing 100871, & Graduate Center for Materials Research, University of Missouri-Rolla, Rolla, Missouri 65409. Large scale growth and magnetic properties of Fe and Fe{sub 3}O{sub 4} nanowires. United States. doi:10.1063/1.2172208.
Yang, J. B., Xu, H., You, S. X., Zhou, X. D., Wang, C. S., Yelon, W. B., James, W. J., Physics Department, National University of Singapore, Singapore 117542, Graduate Center for Materials Research, University of Missouri-Rolla, Rolla, Missouri 65409, School of Physics, Peking University, Beijing 100871, and Graduate Center for Materials Research, University of Missouri-Rolla, Rolla, Missouri 65409. Sat . "Large scale growth and magnetic properties of Fe and Fe{sub 3}O{sub 4} nanowires". United States. doi:10.1063/1.2172208.
@article{osti_20788148,
title = {Large scale growth and magnetic properties of Fe and Fe{sub 3}O{sub 4} nanowires},
author = {Yang, J. B. and Xu, H. and You, S. X. and Zhou, X. D. and Wang, C. S. and Yelon, W. B. and James, W. J. and Physics Department, National University of Singapore, Singapore 117542 and Graduate Center for Materials Research, University of Missouri-Rolla, Rolla, Missouri 65409 and School of Physics, Peking University, Beijing 100871 and Graduate Center for Materials Research, University of Missouri-Rolla, Rolla, Missouri 65409},
abstractNote = {Fe and Fe{sub 3}O{sub 4} nanowires have been synthesized by thermal decomposition of Fe(CO){sub 5}, followed by heat treatments. The Fe wires are formed through the aggregation of nanoparticles generated by decomposition of Fe(CO){sub 5}. A core-shell structure with an iron oxide shell and Fe core is observed for the as-prepared Fe wires. Annealing in air leads to the formation of Fe{sub 2}O{sub 3}/Fe{sub 3}O{sub 4} wires, which after heat treatment in a N{sub 2}/alcohol atmosphere form Fe{sub 3}O{sub 4} wires with a sharp Verwey [Nature (London) 144, 327 (1939)] transition at 125 K. The Fe{sub 3}O{sub 4} wires have coercivities of 261 and 735 Oe along the wire axis at RT and 5 K, respectively. The large increase of coercivity at 5 K as compared to RT is due to the increase of anisotropy resulting from the Verwey transition.},
doi = {10.1063/1.2172208},
journal = {Journal of Applied Physics},
number = 8,
volume = 99,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
  • This work describes the synthesis and magnetic-optical properties of Fe{sub 3}O{sub 4} nanowires decorated by CdTe quantum dots. The composite nanowires with a length of 1 {mu}m and an average diameter of 23{+-}3 nm were prepared in a high yield through the preferential growth of Fe{sub 3}O{sub 4} on CdTe quantum dots using ethylenediamine as template. Their growth mechanism was discussed based on the results of control experiments. Studies on the optical and magnetic properties of the composite nanowires reveal that they assume not only yellow-green emission feature but also room temperature ferromagnetism. - Graphical abstract: The long and flexiblemore » CdTe quantum dots-decorated Fe{sub 3}O{sub 4} nanowires assume not only room temperature ferromagnetism but also strong luminescent effect.« less
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  • Magnetic properties of the quadruple perovskite solid solutions Ca{sub 1–x}Y{sub x}Cu{sub 3}Fe{sub 4}O{sub 12} and Y{sub 1–y}Ce{sub y}Cu{sub 3}Fe{sub 4}O{sub 12} are investigated. Ca{sub 1–x}Y{sub x}Cu{sub 3}Fe{sub 4}O{sub 12} shows continuous increase in the ferromagnetic transition temperature as x increases. Y{sub 1–y}Ce{sub y}Cu{sub 3}Fe{sub 4}O{sub 12} exhibits a ferromagnetic-antiferromagnetic transition in the vicinity of y = 0.5. These observations demonstrate the electron doping effect on magnetic properties of charge-disproportionated ACu{sub 3}Fe{sub 4}O{sub 12} phases.
  • Epitaxial Fe{sub 3}O{sub 4} thin films were grown on TiN buffered Si(001), Si(110), and Si(111) substrates by dc reactive sputtering deposition. Both Fe{sub 3}O{sub 4} films and TiN buffer are fully epitaxial when grown at substrate temperatures above 150 deg. C, with textured single phase Fe{sub 3}O{sub 4} resulting from room temperature growth. The initial sputtered Fe{sub 3}O{sub 4} formed nuclei islands and then coalesced to epitaxial columnar grains with increasing film thickness. The magnetization decreases and the coercive field increases with decreasing film thickness. There is no in-plane magnetic anisotropy of epitaxial Fe{sub 3}O{sub 4}(001) on Si(001) but Fe{submore » 3}O{sub 4} films grown on Si(110) and Si(111) substrates show uniaxial in-plane magnetic anisotropy.« less
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