Tuning of magnetic properties in Co–Zn ferrite nanocrystals synthesized by a size controlled co-precipitation method

Abstract

CoxZn1−xFe2O4 (0.5 ≤ x ≤ 1.0) nanocrystals have been synthesized by conventional and a modified size-controlled coprecipitation method and characterized by X-ray diffraction, transmission electron microscopy, vibrating sample magnetometry, and Mössbauer spectroscopy. The control of the oversaturation conditions in the reacting solution, favored by the control of the flow rate at which the reactants were contacted, promoted heterogeneous nucleation and hence crystal growth, as evidenced by XRD measurements. The size-controlled synthesis route also allowed the tuning of the maximum magnetization and the coercivity, which increased by a factor of five. The demagnetization temperature was found to be strongly dependent on the Co-content and crystal size and varied between 106 °C and 540 °C. Mössbauer spectroscopy confirmed the strong influence of the synthesis conditions on the superparamagnetic fraction in the samples.

A novel laser assisted structure refinement of Co0.5Zn0.5Fe2O4

“…The magnetic and electrical properties of Co-Zn ferrites are well known and have been discussed extensively in the literature [21,22]. In this work the as-synthesized sample (without laser treatment) showed some extra peaks thereby suggesting the use of some structure refinement method.…”

Exploration of the role of nanoferrite load and particle size on the rheometric, mechanical, and dielectric properties of (Co0.2Zn0.8Fe2O4/NBR) nanocomposites

“…Moreover, (Co 0.2 Zn 0.8 Fe 2 O 4 /NBR) nanocomposites with ferrite filler loads (2,4,6,8,10,12,14,20,25, and 30 phr) were prepared. The chemicals and methods for all preparations are as we mentioned in previous research.…”

“…[9] The structural and magnetic properties of Co 1Àx Zn x Fe 2 O 4 (0.5 ≤ x ≤ 1.0) nanoparticles were studied by many authors. [10,11] Furthermore, Polycrystalline ferrites with general formula Co 1Àx Zn x Fe 2 O 4 (x = 0 to 1) were obtained by solid-state reaction technique where the values of longitudinal, Young, bulk, and shear moduli all decreased with zinc concentration. [12] The addition of Zn led to decrease the crystallite size and increase the lattice parameter for Co 1Àx Zn x Fe 2 O 4 ferrite series synthesized by citrate precursor method.…”

“…The novelty here is that we want to determine the optimum load of Co-Zn ferrite and optimum particle size of such a load (not the optimum Zn concentration in the ferrite chemical formula as the previous study). So, in this study, Co 0.2 Zn 0.8 Fe 2 O 4 ferrite is added with different loads (2,4,6,8,10,12,14,20,25, and 30 phr) to determine the optimum load and then study the effect of the particle size of that load on the different mechanical and dielectric properties of the nanocomposite. Our goal is to achieve more enhancements of the mechanical and dielectric properties of NBR which makes it more qualified to be used in many applications such as data transmission and shielding.…”

Statistical characterization of cobalt–zinc ferrite doped with gadolinium ions

“…The corresponding average crystal size was around 35 nm. This rising trend in coercivity can be explained in terms of the enlargement of the crystal within the single magnetic domain region [8][9] and the eventual variation in the ionic distribution in the ferrite lattice. This hypothesis will be corroborated by Mo¨ssbauer analyses and the results will be reported elsewhere in the future.…”