Effect of Ce{sup 3+} Ion on Structural and Hyperfine Interaction Studies of Co{sub 0.5}Ni{sub 0.5}Fe{sub 2−x}Ce{sub x}O{sub 4} Ferrites: Useful for Permanent Magnet Applications

Journal Article · Fri Mar 15 04:00:00 EDT 2019 · Journal of Superconductivity and Novel Magnetism

DOI:https://doi.org/10.1007/S10948-018-4752-2· OSTI ID:22919566

Srinivasamurthy, K. M. ^[1]; Kubrin, S. P. ^[2]; Matteppanavar, Shiddaling ^[3]; Sarychev, D. A. ^[2]; Rudraswamy, B. ^[1]

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1. Bangalore University, Department of Physics (India)
2. Southern Federal University, Research Institute of Physics (Russian Federation)
3. M. S. Ramaiah University of Applied Sciences, Department of Physics (India)

Nanoparticles of Co{sub 0.5}Ni{sub 0.5}Fe{sub 2−x}Ce{sub x}O{sub 4} (where x = 0.0, 0.01, 0.015 and 0.02) ferrites are prepared by the modified solution combustion method using a mixture of fuels and are characterized to understand their structural, microstructural and magnetic properties. The X-ray diffraction is used to confirm the formation of a single-phase cubic spinel structure. The average crystallite sizes are calculated using the Scherrer formula and are found to be less than 50 nm. The microstructural features are obtained by the scanning electron microscopy, and the compositional analysis is done by using the energy-dispersive spectroscopy. The transmission electron microscopy (TEM) investigations show that the synthesized ferrites are made up of very fine spherical nanoparticles. The influence of a rare-earth element (Ce{sup 3+}) on the magnetic properties of the samples was studied using the Mössbauer spectroscopy. The Mössbauer spectroscopy reveals the formation of broadened Zeeman lines and quadrupole-split lines and the presence of the Fe{sup 3+} charge state at B sites in the samples. The quadrupole splitting shows that the orientation of the magnetic hyperfine field with respect to the principle axes of the electric field gradient was random. The magnetic hyperfine field values indicate that the A sites have more A-O-B superexchange interactions than the B sites. The coexistence of magnetic sextet and a doublet component on the room-temperature spectra suggests superparamagnetic properties of the nanoparticles. The low-temperature (15 K) Mössbauer spectroscopy explores the paramagnetic relaxation in the nanoparticles. The area under the sextet refers to Fe{sup 3+} concentrations in the tetrahedral and octahedral sites of the ferrite. This study confirms that the Ce{sup 3+} substitution of Fe{sup 3+} only for octahedron sites causes the decrease in Fe-O-Fe arrangement. The effect of Ce{sup 3+} doping on the magnetic properties of Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} is examined from the vibrating sample magnetometry (VSM) spectra. Saturation magnetization values are decreased initially and then increased, as result of Ce{sup 3+} doping. This can be explained by Neel’s two-sub-lattice model. Further, the value of coercivity is found to be increasing with increasing Ce{sup 3+} concentration. The obtained results of M-H loop with improved coercivity (from 851 to 1039 Oe) by Ce{sup 3+} doping of Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} demonstrate the usefulness for permanent magnet applications.

• OSTI ID: 22919566
• Journal Information: Journal of Superconductivity and Novel Magnetism, Journal Name: Journal of Superconductivity and Novel Magnetism Journal Issue: 3 Vol. 32; ISSN 1557-1939
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CERIUM ADDITIONS
COBALT COMPOUNDS
COERCIVE FORCE
FERRITES
MAGNETIC PROPERTIES
MAGNETIZATION
MICROSTRUCTURE
MOESSBAUER EFFECT
NANOPARTICLES
NICKEL COMPOUNDS
PARAMAGNETISM
PERMANENT MAGNETS
RELAXATION
SCANNING ELECTRON MICROSCOPY
SUPERPARAMAGNETISM
TEMPERATURE RANGE 0013-0065 K
TRANSMISSION ELECTRON MICROSCOPY
VIBRATING SAMPLE MAGNETOMETERS
X-RAY DIFFRACTION
ZEEMAN EFFECT