Structural, dielectric and magnetic properties of nickel substituted cobalt ferrite nanoparticles: Effect of nickel concentration

Abstract

Microstructure and magnetic properties of MFe 2 O 4 (M = Co, Ni, and Mn) ferrite nanocrystals prepared using colloid mill and hydrothermal method Journal of Applied Physics 117, 17A328 (2015) Nickel substituted cobalt ferrite nanoparticles with composition Co 1−x Ni x Fe 2 O 4 (0.0≤x≤1.0) was synthesized using simple, low temperature auto combustion method. The X-ray diffraction patterns reveal the formation of cubic phase spinel structure. The crystallite size varies from 30-44 nm with the nickel content. Porous and agglomerated morphology of the bulk sample was displayed in the scanning electron microscopy. Micro Raman spectroscopy reveals continuous shift of E g and E g (2) stokes line up to 0.8 Ni substitution. The dispersion behavior of the dielectric constant with frequency and the semicircle nature of the impedance spectra show the cobalt nickel ferrite to have high resistance. The ferromagnetic nature is observed in all the samples, however, the maximum saturation magnetization was achieved by the 0.4 Ni substituted cobalt ferrite, which is up to the 92.87 emu/gm at 30K. C 2015 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License. [http://dx

Electrical Conduction Mechanism and Dielectric Properties of Spherical Shaped Fe3O4 Nanoparticles Synthesized by Co-Precipitation Method

“…Most of the literature only confirm that Jonscher’s power law can be used to describe the electrical conductivity of ferrites [ 27 ]. In their work, Velhal et al showed that electrical conduction can be related to small polarons in cobalt ferrite nanoparticles; however, this result has not been combined with the previously described electrical conduction mechanism associated with hopping of electrons, and has not been confirmed by an analysis of s ( T ) behavior [ 28 ]. Moreover, many works only attributed variations of AC conductivity with frequency to the hopping of electrons between Fe 3+ and Fe 2+ ions and conduction by small polarons, without using the Jonscher’s power law, and determining the conduction mechanism model or hopping energy value [ 15 , 16 , 29 ].…”

Structural, magnetic and dielectric properties of ultrafine nickel substituted cobalt ferrite− reduced graphene oxide nanocomposites

“…NCF shows a shift towards higher angles at 57.03 o and 63.11 o correspond to (511) and (440) planes. The shift is due to the smaller ionic radius (0.069 nm) of Ni 2+ , than that of (0.072 nm) Co 2+ , with lower lattice parameter and lattice volume [5]. respectively.…”

Progress, Challenges and Opportunities in Divalent Transition Metal-Doped Cobalt Ferrites Nanoparticles Applications

“…Considering its good chemical and thermal stability, high electrical resistivity, magnetic anisotropy, high H C , moderate M S , superparamagnetism, ferrimagnetism and dielectric structure, the Ni doped Co ferrite is a good candidate for microwave devices and data storage [71]. The Co 1−x Ni x Fe 2 O 4 (0.0 ≤ x ≤ 1.0) synthesized using simple, low temperature auto-combustion method showed high resistance.…”

“…The Co 1−x Ni x Fe 2 O 4 (0.0 ≤ x ≤ 1.0) synthesized using simple, low temperature auto-combustion method showed high resistance. As the Ni content increases, the dielectric constant and loss tangent decrease and remain constant at higher frequencies, while conductivity increases with increasing frequency [71]. The use as supercapacitors of mixed ternary Cu-Co-Ni ferrites obtained by sol-gel synthesis and citric acid as chelating agent was investigated by Bhujun et al [72].…”