Co2+ substituted Mg–Cu–Zn ferrite: Evaluation of structural, magnetic, and electromagnetic properties

Abstract

We report the synthesis of Co 2+ substituted Mg-Cu-Zn ferrite via citrate gel combustion process and thereby its structural, transport, and magnetic properties for the use in electromagnetic energy absorption application. The polycrystalline ferrite system is investigated by interplay of stoichiometric composition with Mg 0.25-x Co x Cu 0.25 Zn 0.5 Fe 2 O 4 (0 ≤ x ≤ 0.25). Structural investigations using X-ray diffraction (XRD) and selected area electron diffraction (SAED) reveal the formation of spinel structure with linear growth of lattice constant due to Co 2+ substitution. The microstructural analysis (TEM and SEM) depicts the dense microstructure with the average grain size of 0.42-1.25 µm. The elemental analysis (EDS) confirms the elemental composition of the as-prepared ferrite with respect to the initial concentrations of the synthetic composition used. The observed variations in initial permeability ( i  ) and magnetic moment ( ) are explained based on deviation in saturation magnetization ( s B n M ), anisotropy constant ( 1 K ), density values, and exchange interaction. The temperature dependence of DC resistivity confirms the semiconducting behavior of the as-prepared ferrite material, with an increase in the DC resistivity by an incorporation of cobalt. Furthermore, the effects of adding Co 2+ on the Curie temperature, frequency dependent dielectric properties of the ferrite material are also discussed.

Influenced of Cu<sup>2+</sup> Doped on Structural, Morphological and Optical Properties of Zn-Mg-Fe<sub>2</sub>O<sub>4</sub> Ferrite Prepared by Sol-Gel Method

“…The results of samples ferrites of Zn 0.5 Cu x Mg 0.5−x Fe 2 O 4 with (X = 0.0, 0.1, 0.2, 0.3, and 0.4) are illustrated in Figure 1. The spectra showed the presence of peaks that correspond to (002), (110), (111), (310), (112), and (002) planes, where highly intense peak at (002) plane confirms cubic spinel structure of as-prepared material [11]. The lattice parameters constants (a) are found to decrease from (8.906 -8.35) Åas the value of X increases.…”

“…As magnesium has larger atomic weight than copper, the density of the sample without Cu doping (X = 0) is observed to be lower than that of Cu 2+ doping (X = 0.4) sample. The values of weight and atomic are given in Table 2 [11]. The increase in density may be due to the ionic of constituent ions.…”

“…Spinel ferrites are examples for doping ferrites [10]. Several synthetic routes were employed for the development of aforementioned mixed ferrite system, namely sol-gel, co-precipitation, hydrothermal and the auto-emulsion methods [11].…”

Structural, thermomagnetic, and dielectric properties of Mn0.5Zn0.5GdxFe2−xO4 (x = 0, 0.025, 0.050, 0.075, and 0.1)

“…where 5585 is the magnetic factor and MW is the molecular weight. It is noticed that maximum magnetization decreases continuously from 39. primarily due to superexchange (A-B) interactions developed between tetrahedral and octahedral sites through oxygen ions [24]. Hence, the net magnetization between oppositely magnetized A and B sublattices is given by…”

“…This contributes to higher values of dielectric constant at lower frequencies. Further, when the frequency of applied field is increased, the electron exchange between Fe 3+ and Fe 2+ ions cannot follow the rapidly changing field [24]. The electron will hardly transfer before the alternating field reverses and as a result probability of electrons reaching the grain boundary becomes very less.…”