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Title: Mechanosynthesis of zinc ferrite in hardened steel vials: Influence of ZnO on the appearance of Fe(II)

Abstract

Nanocrystalline ZnFe{sub 2}O{sub 4} spinel powders are synthesized by high-energy ball milling, starting from a powder mixture of hematite ({alpha}-Fe{sub 2}O{sub 3}) and zincite (ZnO). The millings are performed under air using hardened steel vials and balls. X-ray diffraction and Moessbauer spectrometry are used to characterize the powders. A spinel phase begins to appear after 3 h of milling and the synthesis is achieved after 9 h. Phase transformation is accompanied by a contamination due to iron coming from the milling tools. A redox reaction is also observed between Fe(III) and metallic iron during milling, leading to a spinel phase containing some Fe(II). The mechanism for the appearance of this phase is studied: ZnO seems to have a non-negligeable influence on the synthesis, by creating an intermediate wuestite-type phase solid solution with FeO.

Authors:
 [1];  [1];  [2]
  1. Institut des Materiaux, Universite de Rouen, LASTSM, BP12 76801 Saint Etienne du Rouvray, Cedex (France)
  2. Institut des Materiaux, Universite de Rouen, LASTSM, BP12 76801 Saint Etienne du Rouvray, Cedex (France). E-mail: malick.jean@univ-rouen.fr
Publication Date:
OSTI Identifier:
20784756
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 178; Journal Issue: 11; Other Information: DOI: 10.1016/j.jssc.2005.07.033; PII: S0022-4596(05)00350-6; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CRYSTALS; FERRITES; HEMATITE; IRON OXIDES; MOESSBAUER EFFECT; NANOSTRUCTURES; PHASE TRANSFORMATIONS; SOLID SOLUTIONS; SPINELS; STEELS; SYNTHESIS; X-RAY DIFFRACTION; ZINC COMPOUNDS; ZINC OXIDES

Citation Formats

Verdier, Thomas, Nachbaur, Virginie, and Jean, Malick. Mechanosynthesis of zinc ferrite in hardened steel vials: Influence of ZnO on the appearance of Fe(II). United States: N. p., 2005. Web. doi:10.1016/j.jssc.2005.07.033.
Verdier, Thomas, Nachbaur, Virginie, & Jean, Malick. Mechanosynthesis of zinc ferrite in hardened steel vials: Influence of ZnO on the appearance of Fe(II). United States. doi:10.1016/j.jssc.2005.07.033.
Verdier, Thomas, Nachbaur, Virginie, and Jean, Malick. Tue . "Mechanosynthesis of zinc ferrite in hardened steel vials: Influence of ZnO on the appearance of Fe(II)". United States. doi:10.1016/j.jssc.2005.07.033.
@article{osti_20784756,
title = {Mechanosynthesis of zinc ferrite in hardened steel vials: Influence of ZnO on the appearance of Fe(II)},
author = {Verdier, Thomas and Nachbaur, Virginie and Jean, Malick},
abstractNote = {Nanocrystalline ZnFe{sub 2}O{sub 4} spinel powders are synthesized by high-energy ball milling, starting from a powder mixture of hematite ({alpha}-Fe{sub 2}O{sub 3}) and zincite (ZnO). The millings are performed under air using hardened steel vials and balls. X-ray diffraction and Moessbauer spectrometry are used to characterize the powders. A spinel phase begins to appear after 3 h of milling and the synthesis is achieved after 9 h. Phase transformation is accompanied by a contamination due to iron coming from the milling tools. A redox reaction is also observed between Fe(III) and metallic iron during milling, leading to a spinel phase containing some Fe(II). The mechanism for the appearance of this phase is studied: ZnO seems to have a non-negligeable influence on the synthesis, by creating an intermediate wuestite-type phase solid solution with FeO.},
doi = {10.1016/j.jssc.2005.07.033},
journal = {Journal of Solid State Chemistry},
number = 11,
volume = 178,
place = {United States},
year = {Tue Nov 15 00:00:00 EST 2005},
month = {Tue Nov 15 00:00:00 EST 2005}
}
  • Research highlights: {yields} Cobalt-zinc ferrite was prepared by combustion method. {yields} Properties of the sample were characterized by several techniques. {yields} Curie temperature was determined to be 350 {sup o}C. -- Abstract: Cobalt-zinc ferrite (Co{sub 0.8}Zn{sub 0.2}Fe{sub 2}O{sub 4}) was prepared by combustion method, using cobalt, zinc and iron nitrates. The crystallinity of the as-burnt powder was developed by annealing at 700 {sup o}C. Crystalline phase was investigated by XRD. Using Williamson-Hall method, the average crystallite sizes for nanoparticles were determined to be about 27 nm before and 37 nm after annealing, and residual stresses for annealed particles were omitted.more » The morphology of the annealed sample was investigated by TEM and the mean particle size was determined to be about 30 nm. The final stoichiometry of the sample after annealing showed good agreement with the initial stoichiometry using atomic absorption spectrometry. Magnetic properties of the annealed sample such as saturation magnetization, remanence magnetization, and coercivity measured at room temperature were 70 emu/g, 14 emu/g, and 270 Oe, respectively. The Curie temperature of the sample was determined to be 350 {sup o}C using AC-susceptibility technique.« less
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