Preparation and characterization of nanosize nickel-substituted cobalt ferrites (Co{sub 1-} {sub x} Ni {sub x} Fe{sub 2}O{sub 4})
- Institute Instrumentation Centre, Indian Institute of Technology, Roorkee, Roorkee-247 667 (India)
- Department of Physics, Indian Institute of Technology, Roorkee, Roorkee-247 667 (India)
Nanosize nickel-substituted cobalt ferrites were prepared using aerosol route and characterized by TEM, XRD, magnetic and Moessbauer spectroscopy. The particle size of as obtained samples was found to be {approx}10 nm which increases upto {approx}80 nm on annealing at 1200 deg. C. The unit cell parameter 'a' decreases linearly with the nickel concentration due to smaller ionic radius of nickel. The saturation magnetization for all the samples after annealing at 1200 deg. C lies in the range 47.6-84.5 emu/g. Room temperature Moessbauer spectra of as obtained samples exhibit a broad doublet, suggesting super paramagnetic nature of the sample. The broad doublet is further resolved into two doublets corresponding to the iron atoms residing at the surface and internal regions of the particle. The samples annealed at 1200 deg. C showed broad sextet, which is resolved into two sextets, corresponding to tetrahedrally and octahedrally coordinated Fe cations. Cation distribution calculated using XRD and Moessbauer data indicates a decrease in Fe{sup 3+}(oct.)/Fe{sup 3+}(tet.) ratio with increasing nickel concentration. - Graphical abstract: Fig. 4. X-ray diffraction pattern of Co{sub 1-} {sub x} Ni {sub x} Fe{sub 2}O{sub 4} after annealing at 1200 deg. C.
- OSTI ID:
- 20721741
- Journal Information:
- Journal of Solid State Chemistry, Vol. 178, Issue 10; Other Information: DOI: 10.1016/j.jssc.2005.07.020; PII: S0022-4596(05)00336-1; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
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