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Title: Structural and magnetic properties of yttrium and lanthanum-doped Ni-Co and Ni-Co-Zn spinel ferrites

Abstract

Rare earth doping of Co-rich spinel ferrites is investigated through the preparation of two groups of polycrystalline Ni-Co and Ni-Co-Zn ferrites, where Fe is partly substituted by Y and La. The characterization of the sintered ferrites by means of X-ray powder diffraction and Rietveld profile analysis, indicates the subtle expansion of the spinel unit cell and the cation redistribution in the doped ferrites in order to accommodate the incorporation of Y and La in the lattice. The impurity traces, detected only in the Ni-Co-Zn group, is ascribed to the Zn population in the tetrahedral A-sites impeding the cation transfer. Moreover, the examined microstructure of the doped Ni-Co samples comprises enlarged and more homogeneous grains, whereas grain growth is moderated in the doped Ni-Co-Zn ferrites. The discussed characteristics of the crystal and magnetic structure along with the morphological aspects define the impact of Y and La doping on the static magnetic properties of Ni-Co and Ni-Co-Zn ferrites, saturation magnetization MS and coercivity HC, which were extracted from the respective hysteresis loops.

Authors:
 [1];  [2]
  1. Laboratory of Inorganic Materials, Centre for Research and Technology-Hellas, 57001, Thermi (Greece)
  2. Laboratory of Materials for Electrotechnics, Aristotle University of Thessaloniki, 54124, Thessaloniki (Greece)
Publication Date:
OSTI Identifier:
22390529
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1627; Journal Issue: 1; Conference: 14. Electroceramics Conference, Bucharest (Romania), 16-20 Jun 2014; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; COERCIVE FORCE; DOPED MATERIALS; FERRITES; GRAIN GROWTH; HYSTERESIS; LANTHANUM; MAGNETIC PROPERTIES; MAGNETIZATION; MICROSTRUCTURE; POLYCRYSTALS; SPINELS; X-RAY DIFFRACTION; YTTRIUM

Citation Formats

Stergiou, Charalampos, E-mail: stergiou@cperi.certh.gr, and Litsardakis, George, E-mail: lits@eng.auth.gr. Structural and magnetic properties of yttrium and lanthanum-doped Ni-Co and Ni-Co-Zn spinel ferrites. United States: N. p., 2014. Web. doi:10.1063/1.4901668.
Stergiou, Charalampos, E-mail: stergiou@cperi.certh.gr, & Litsardakis, George, E-mail: lits@eng.auth.gr. Structural and magnetic properties of yttrium and lanthanum-doped Ni-Co and Ni-Co-Zn spinel ferrites. United States. doi:10.1063/1.4901668.
Stergiou, Charalampos, E-mail: stergiou@cperi.certh.gr, and Litsardakis, George, E-mail: lits@eng.auth.gr. 2014. "Structural and magnetic properties of yttrium and lanthanum-doped Ni-Co and Ni-Co-Zn spinel ferrites". United States. doi:10.1063/1.4901668.
@article{osti_22390529,
title = {Structural and magnetic properties of yttrium and lanthanum-doped Ni-Co and Ni-Co-Zn spinel ferrites},
author = {Stergiou, Charalampos, E-mail: stergiou@cperi.certh.gr and Litsardakis, George, E-mail: lits@eng.auth.gr},
abstractNote = {Rare earth doping of Co-rich spinel ferrites is investigated through the preparation of two groups of polycrystalline Ni-Co and Ni-Co-Zn ferrites, where Fe is partly substituted by Y and La. The characterization of the sintered ferrites by means of X-ray powder diffraction and Rietveld profile analysis, indicates the subtle expansion of the spinel unit cell and the cation redistribution in the doped ferrites in order to accommodate the incorporation of Y and La in the lattice. The impurity traces, detected only in the Ni-Co-Zn group, is ascribed to the Zn population in the tetrahedral A-sites impeding the cation transfer. Moreover, the examined microstructure of the doped Ni-Co samples comprises enlarged and more homogeneous grains, whereas grain growth is moderated in the doped Ni-Co-Zn ferrites. The discussed characteristics of the crystal and magnetic structure along with the morphological aspects define the impact of Y and La doping on the static magnetic properties of Ni-Co and Ni-Co-Zn ferrites, saturation magnetization MS and coercivity HC, which were extracted from the respective hysteresis loops.},
doi = {10.1063/1.4901668},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1627,
place = {United States},
year = 2014,
month =
}
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