Effect of Zn Substation on Structural and Magnetic Properties of Cu-Ferrites Nanoparticles

In this research prepared samples of CuZn-ferrites were substation of copper ions by zinc ions as a composition formula Cu 1-x Zn x Fe 2 O 4 ferrite (with x = 0.0, 0.1, 0.2, 0.3) and studying the properties of composition using FTIR spectroscopy established creation of spinel ferrite and presented the features of absorption bands around 561.29-405 cm −1 . X-ray diffraction (XRD) exposed that the structure of these nano particles is spinel and crystallite size lies in the range (12.22–23.9) nm. observed when added zinc ions, found increase in particle size and lattice constant while decrease in Xrd-density, and also have been identified the behavior of material Ferrite in low frequencies permeability magnetic used LCR meter , found when increasing the frequency (1-200) KHz decries in magnetic permeability (μ′) this usual behavior in ferrites and observed a significant increase in magnetic permeability when increasing zinc ions due to the effect of zinc on the internal structure of copper ferrite. At Low frequency institute that the permeability raises with Zn contented rise from (0 - 0.3) in Cu-ferrites.


INTRODUCTION
errites with spinel structure very important magnetic materials having eventual applications and the practical research. Copper -Zinc Ferrites are a polycrystalline complex system combined of crystallites, grain boundaries and pores [1], with excellent soft magnetic properties and used in electronic and telecommunication industries. [2]for the most part of bulk CuFe 2 O 4 had an inverse spinel structure, with Cu 2+ occupying B sites , as ZnFe 2 O 4 was commonly be a normal spinel and Zn 2+ ions preferentially occupy A sites while Fe 3+ ions would be displace from A sites for B sites. Zn-substitution will be change a cations in chemical composition and a different distribution of a cations between A and B sites. That cause the magnetic properties of spinel ferrites will change with changing cation distribution. , [3] ferrite with polycrystalline has received special interest because of their excellent magnetic properties and high electrical resistivity under a large range of frequencies; from a few hundred Hz to more than a few GHz. ferrites Spinel type was usually used in several electronic and magnetic devices because of their high magnetic [4,5] permeability and low magnetic losses. Cu-Zn ferrites were considered as the most significant magnetic oxides because of tailoring flexibility in the properties of magnetic, use at higher frequency, low cost, high mechanical hardness and high corrosion resistivity. The intent of material was providing permittivity bigger than μ 0 since the inductor may become further densely with turn of wires [7]. These could reduction losses of skin effects in the wire and reduction coupled to other inductive component in circuits, but the losses of circuit might be imperfect by magnetic materials themselves [8].the aim of that research is to study the effect of zinc ions in the in magnetic permeability (μ′) at low frequency  KHz and also to study that effect in the structure properties.

Experimental
The ferrite Cu  (2 hour.).Where the powder pressed by holy circler die toroid formed the samples by pressed the powder and sintered at 860˚C for 4 hour in air and then cools in the furnace. After that wrap the wire around toroid (samples) for preparer them to masseur the indication by use LCR meter. At room temperature with the LCR meter the inductance of the toroid (ring) sample assessed in the low frequency range (1 -200) kHz. The permeability μ' is evaluated by equ. (1). [4] μ ′ = ………………. (1) Where, L is Inductance, N is turns No. Ht is core Height, D O is core Outer diameter D i is core Inner diameter, 2x10 -7 is Conversion factor.
Phase analysis was done by (Philips PW 1050) XRD, diffract meter has been used.Where used the equation (1) for a cubic system for most intensity peak (311) to collected the lattice parameter (a); a 2 = (h 2 +k 2 +l 2 ). d 2 ……… (2) h,k,l is miler index, d is the inter planer spacing.
Average particle size (D X ) was calculated by using Debye-Scherrer equation, λ is wave length of XRD, β is broadening of the diffraction peak, θ is diffraction angle, the calculate crystallite size from broadening of the (311) XRD peak and equation (3) used to calculate X-ray density (ρ x   ): M W is molecule Wight, N a is Avogadro's number, and a is lattice constant.
To characterize the samples with a primary the sintered ferrites microstructures take by using scanning electron microscopy (SEM, the VEGA Easy Probe)). The micrograph was taking on flat faces of the pellets designed sample. As a result, the mean particle size was found in the range 0f (12.22-23.9nm) calculated from the peak (311) of the XRD diffract gram employing by Scherrer's formula where the piratical size found increase when Zn content increased as seen in fig (2). Hence calculate the X-ray density and lattice constant by used of a X-ray data. The lattice constant calculated by the Nelson R. extrapolated technique [5], since lattice constant was rising with further add of Zn 2+ ion as give in Table (2), that because of ionic radius of Zn 2+ ions (R Zn2+ = 0.82 A) was bigger than Cu 2+ ions (R Cu2+ = 0.73 Å) that cause increasing a lattice constant which can deals with ionic size variation. [10].
Decreasing trends in X-ray density observe with increase Zn substance as shown in Figure 3. This because of rise of Oxygen vacancies that show main part in accelerated densifications [11,12], where decreasing in Oxygen ion (anion) diffusion could impede the densifications.
Also observed as show in figure (3) the density increase when the sintering the samples because of evaporate the Zn ions and consequently the pores decrease through diffusion kinetics.   [14], and that lead to molecular magnetic moment could be greater than before addition a little of Zn +2 in mixed ferrite. The substituted of Zn 2+ which is nonmagnetic (diamagnetic) in spite of that but Zn +2 has great effect in magnetic permeability because of effect in ion distribution in magnetic features of CuFe 2 O 4 where the Zn +2 ions occupy the tetrahedral a-site replace the identical quantity of Fe 3+ to octahedral bsites. This could give increases B-sites a further magnetized. As effect of the B-B interaction tends to be anti-ferromagnetic [15]. It was observed the strong A-B interface was the reasons of the spins in the B-sites were parallels align. The Permeability dependence on molecular magnetism where be forcing on domain wall because of the magnetic field and the resulting magnetization changes are both relative to permeability.

Microstructure
All ferrites powder calcint at 500 0 C have been investigation.as seen in Fig(7) the SEM picture of ferrites powder have actually seam outfit structure where the powders look like ash and the pores is clear in all samples, irregular shape and size of particles was found , and see also the particle will be more picket when the Zn content be high .

CONCLUSION
During the research Investigated experimentally how properties of spinel Cu-ferrites are affected by doping of Zn. Where prepared these samples through the sol-gel method, and performed various structural and magnetic. The existence of Zn ions causes significant changes in the structure and magnetic properties in Cu ferrite, where particle size and lattice constant found a clear increase but in XRD density was decrease , were observed the effect of ions zinc added to these properties, and also it has been identified on the behavior of Ferrite material in low frequencies during permeability magnetic account, found when increasing the frequency the permeability decrease  KHz this usual behavior of ferrites materials.