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Influence of doping on magnetic and electromagnetic properties of spinel ferrites.

Influence of doping on magnetic and electromagnetic properties of spinel ferrites.

Authors :
Nag, Abanti
Bose, Rapaka SC.
ManojKumar, A.
Venu, K.S.
Singh, Hema
Source :
Ceramics International. Oct2023, Vol. 49 Issue 20, p33099-33110. 12p.
Publication Year :
2023

Abstract

In this study, spinel Ni 0.5 Zn 0.5 Fe 2 O 4 doped with transition metal ions as well as rare-earth ions Ni 0.4 Zn 0.4 M′ 0.2 Fe 2 O 4 (M′ = Cu, Dy, Gd and Lu) and M″ 0.5 Zn 0.5 Fe 2 O 4 (M″ = Ni, Mn and Co) are developed using the sol-gel auto-combustion route, and the role of substitution on electromagnetic properties is investigated. The powder X-ray diffraction accompanied by Rietveld refinement signifies a single-phase spinel ferrite that belongs to Fd- 3 m space group for all the compositions. Rietveld refinement confirms that doped Cu2+, Dy3+, Gd3+ and Lu3+ ions are at random distribution between spinel tetrahedral and spinel octahedral sites against their preferential occupancy. The saturation magnetisation (M S) of Ni 0.5 Zn 0.5 Fe 2 O 4 (M S = 50.5 emu/g) increased with partial doping showing M S = 60.08 emu/g for transition-metal doped Ni 0.4 Zn 0.4 Cu 0.2 Fe 2 O 4 and M S = 109.7 emu/g for rare-earth doped Ni 0.4 Zn 0.4 Dy 0.2 Fe 2 O 4 , which was the highest among all the doped compositions. Doping enhances the dielectric permittivity of Ni 0.5 Zn 0.5 Fe 2 O 4 from 4.2 to 6.5 for Ni 0.4 Zn 0.4 Cu 0.2 Fe 2 O 4 and 7.7 for Ni 0.4 Zn 0.4 Dy 0.2 Fe 2 O 4. Further, the reflection coefficient (R L) of all the doped compositions of Ni 0.4 Zn 0.4 M′ 0.2 Fe 2 O 4 (M′ = Cu, Dy, Gd and Lu) was less than −8 dB (85% absorption) throughout the frequency band of 8–12 GHz with an optimum material thickness of 3.5 mm. Transition metal ion doped Ni 0.4 Zn 0.4 Cu 0.2 Fe 2 O 4 resulted in further improvement of its absorption characteristics of the incident EM waves with reflection coefficient (R L) less than −10 dB (between 84.15% and 90%) between 10 and 12 GHz at a material thickness of 3.5 mm in the X-band frequency range. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
02728842
Volume :
49
Issue :
20
Database :
Academic Search Index
Journal :
Ceramics International
Publication Type :
Academic Journal
Accession number :
171367967
Full Text :
https://doi.org/10.1016/j.ceramint.2023.08.011