Study of Structural, Morphological and Dielectric Properties of Copper doped Ni 0.3 Cu. V. R. Pande, * R. B. Bhise

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1 Study of Structural, Morphological and Dielectric Properties of Copper doped Ni 0.3 Cu 0.2 Mg 0.3 Zn 0.2 Fe2O4 Nanoferrite using Sol-gel Technique V. R. Pande, * R. B. Bhise Research scholar, JJT University, Jhunjhunu, Rajasthan, INDIA, * Department of Physics, B. J. College, Ale, Tal: Junnar, Dist: Pune, MS, India bhiseramesh@gmail.com Abstract: Nanoferrite Ni 0.3 Cu 0.2 Mg 0.3 Zn 0.2 Fe 2O 4 is synthesized by using sol-gel technique. The prepared sample was characterized and structural properties study using X-ray diffraction and morphological study using Scanning electron microscopy (SEM). The X- RD analysis of the samples sintered at C for 4h shows the cubic spinal structure for ferrites with size distribution from 28 to 36 nm. The energy dispersive scattering pattern obtained for the samples. The spinal ferrites are studied by measuring dielectric constant and dielectric loss at room temperature in the frequency range 100 Hz-5MHz using LCR-Q meter. The dielectric constant and loss tangent decrease with increase in frequency of the applied field. The dielectric constant and loss tangent decreases rapidly with increasing frequency and then reaches to constant value which shows normal ferromagnetic behaviour. Keywords: XRD, Dielectric constant, Dielectric loss, Electrical resistivity, etc. I. INTRODUCTION The polycrystalline Ni, Mg, Cu and Zn soft ferrites are suitable for core materials in micro inductor applications. The most popular applications of ferrite are in optics, electronics, mechanics and other technical fields. Nanoferrites with copper substitution synthesized using sol-gel method are studied in the present work. The sol-gel technique of preparing nanoferrite has many significant advantages such as good stoichiometric control and for the production of ultrafine particle with nanosize distribution in relatively short processing time at lower temperature. The properties of nanoparticles varied from its morphology, size and microstructure and it is important to analyze obtaining conditions and method of synthesis of nanoparticles as well as synthesis of new metal oxides with new properties. Specially we characterize structural properties of doped samples at room temp and sintered at C. The various techniques are employed X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), Fourier transform Infra-Red (FTIR) spectroscopy, Transmission Electron Microscope (TEM). The aim of this research was to obtain Ni Cu Mg Zn ferrite nanoparticles. In this work we analyzed the morphological properties of Ni 0.3 Cu 0.2 Mg 0.3 Zn 0.2 Fe 2O 4 powder synthesized by sol-gel technique. II. MATERIALS AND METHOD Ni 0.3 Cu 0.2 Mg 0.3 Zn 0.2 Fe 2O 4 nanoferrites were prepared by sol-gel method. In this method each sample was prepared by taking desired proportion of precursor nitrates. The precursor solution was prepared using AR grade metal nitrates Ni(NO 3) 2,Cu(NO 3) 2, Mg(NO 3) 2, Zn(NO 3) 2 and Fe(NO 3) 2.The nitrates were initially dissolved separately in minimum amount of water. The precursor solution was prepared by adding all above solutions and continuously stirred for 30 minutes at C. An aqueous solution of citric acid mixed with metal nitrate solution. A required amount of ammonia was slowly added into solution in order to adjust the ph value to about 7 since bare catalysts are employed in order to speed up the reaction. The mixed solution was kept on to a hot plate with continuous stirring at C. After 3 to 4 hrs all water molecules were removed from the mixture. The viscous gel has formed.the gel automatically ignited and burns with glowing flints. The auto combustion was completed within a minute. The result was the brown colored ashes termed as precursor. The prepared powders were sintered at C for four hours to get the final powders for characterization. Page No:989

2 III. RESULTS AND DISCUSSION: Powder x-ray diffraction (X-RD) pattern was carried out on X-ray diffractometer (model Bruker D8) with Cu kα irradiation (λ=1.5405a ). The lattice parameters, crystalline (grain) size of samples were calculated from XRD data. The scanning electron microscope (FEG-SEM) JSM-7600F and transmission electron microscope PHILIPS (model CM200) was used to study the morphology and estimate grain size. The infrared spectra of all samples were recorded in the range cm in FTIR instrument (JASCO MODEL V 670). The dielectric constant (ε ), dielectric loss (ε ) and dielectric loss tangent (tanδ) of all the samples were obtained by using LCR-Q meter (model HP 4284A) as a function of frequency. The frequency was varied from 100 Hz to 5MHz. 3.1 Structural Characterization:- Structural characterization was carried out using diffractometer Bruker with advanced system with a diffracted beam monochromatic Cukα radiation(λ=1.5405a ) source between the Bragg Angles 20 to 80 in steps of 0.04 /sec. The 2θ Vs intensity data obtained from this experiment and plotted graph as shown in fig.1. All Bragg reflections have been indexed which confirm the formation of cubic spinal structure in single phase. The strongest reflection comes from the (311) planes, which denote the spinal phase. The peaks indexed to (220) (311) (400) (422) (333) and (440) planes of cubic unit cell. All planes are allowed planes which indicate the formation of cubic spinal structure in single phase. Fig.1: XRD pattern of the samples sintered at C of Ni 0.3 Cu 0.2 Mg 0.3 Zn 0.2 Fe 2 O 4 The particle size (d) was calculated for all the compositions using the high intensity 311 peak and using Scherer formula. d = Where, λ the wavelength of x-ray radiation, β is Full Width Half Maxima (FWHM) corresponding to maximum peak, θ angle at peak position. Page No:990

3 Table-1: Composition(x), Particle size(d), Lattice constant(a), Volume(V), X-ray density(d x) and specific surface area (S ) of spinal ferrite system dx x d a V S nm A 0 (A 0 ) 3 gm/cm 3 m 2 /gm Parameter (a) for all the composition of Ni 0.3 Cu 0.2 Mg 0.3 Zn 0.2 Fe 2O 4 nanoferrites have been calculated from the values of d- spacing s and are given in table-1. The lattice parameter (a) of individual composition was calculated by using a formula. a= Where a= Lattice constant, (hkl) are the miller indices of crystallographic plane, and d= inter planner spacing. 3.2 SEM Analysis: - The prepared sample is performing scanning electron microscope (SEM) with model-jsm-7600f microscope. We analyzed the structure of Ni 0.3 Cu 0.2 Mg 0.3 Zn 0.2 Fe 2O 4 powder and show typical micrographs in figure-2. Fig.2: SEM micrographs of Ni 0.3 Cu 0.2 Mg 0.3 Zn 0.2 Fe 2 O 4 ferrite sintered at C It can be seen from SEM micrographs various compositions that the morphology of particles is very similar. They indicate that particle size of sample lies in the nanometer range having a spherical shape and narrow size distribution. The energy dispersive scattering (EDAX) pattern obtained for the samples. It may be seen that besides the characteristics peaks of Fe, Ni, Cu, Mg, Zn peaks arising out of the substrate are Carbon and Oxygen. Page No:991

4 Fig-3: EDAX image of Ni 0.3 Cu0.2 Mg 0.3 Zn 0.2 Fe2 O4 3.3 Dielectric properties :- Fig-4 (a): Variation of dielectric constant with log f of Ni 0.3 Cu0.2 Mg 0.3 Zn 0.2 Fe2 O4 Page No:992

5 Fig-4 (b): Variation of dielectric loss with log f of Ni 0.3 Cu0.2 Mg 0.3 Zn 0.2 Fe2 O4 Fig-4 (c): Variation of dielectric loss tangent with log f of Ni 0.3 Cu0.2 Mg 0.3 Zn 0.2 Fe2 O4 The dielectric constant (ε ), dielectric loss (ε ) and dielectric loss tangent (tanδ) were measured by using LCR-Q meter in the frequency range of 100 Hz to 5MHz.The measurements were carried out on a disc shaped pellets using two probe methods at the room temperature. Fig-4 (a,b,c) shows the variation of dielectric constant (ε ) with frequency for the sample. From Figure, it can be seen that the dielectric constant (ε ) decreases with increase in frequency. The behavior of frequency dependence of (ε ) is in very good agreement with the well-known spinal ferrites. The decrease of polarization with increase of frequency may be due to the fact that beyond a certain frequency of dielectric constant decreases with increasing frequency. The variation of dielectric loss (ε ) with log f shows that decreases with increase in frequency. From figure, it can be seen that sample show a normal dielectric behaviour with frequency.the parameter tanδ decreases exponentially with increase in frequency. The decrease in tanδ with increase in frequency is attributed to the fact that the hopping frequency of the charge carrier cannot follow changes of the polarity of the external field beyond a certain frequency. According to the Iwauchi there is a strong co-relation between the conduction mechanism and the dielectric behaviour of ferrites. Page No:993

6 IV. CONCLUSION The sol-gel technique is convenient for the synthesis of nanosize Ni 0.3 Cu 0.2 Mg 0.3 Zn 0.2 Fe 2O 4 ferrite. X ray diffraction pattern confirm that the synthesis of fully crystalline Ni-Mg-Cu-Zn ferrite nanoparticles at high temperatures. The particle sizes of the nanoparticle samples were found to be about 28 to 36 nm on sintering at 400 C. The dielectric constant (ε ), dielectric loss (ε ) and dielectric loss tangent (tanδ) decreases as frequency increases. 5. REFERENCES: 1. Chand J., Kumar Gagan, Kumar P., Sharma S. K., Knobel M., and Singh M. Effect of Gd 3+ doping on magnetic, electric and dielectric properties of MgGd xfe 2 xo 4 ferrites processed by solid state reaction technique. J. Alloys and Compds., 509: , Lakshmi M., Vijaya Kumar K. and Thyagarajan K. Study of the Dielectric Behaviour of Cr-Doped Zinc Nano Ferrites Synthesized by Sol-Gel Method. Advances in Materials Physics and Chemistry, 6: , Srivastava M., Chaubey S. and Ojha A.K. Investigation on Size Dependent Structural and Magnetic Behavior of Nickel Ferrite Nanoparticles Prepared by Sol-Gel and Hydrothermal Methods. Materials Chemistry and Physics, 118: , Kharabe R.G., Devan R.S., Kanamadi C.M. and Chougule B.K.. Dielectric Properties of Mixed Li-Ni-Cd Ferrites. Smart Materials and Structures, 15: 36-39, Nadeem K., Zeb F., Azeem Abid M., Mumtaz M. and Anis ur Rehman M. Effect of Amorphous Silica Matrix on Structural, Magnetic, and Dielectric Properties of Cobalt Ferrite/Silica Nanocomposites. Journal of Non-Crystalline Solids, 400: 45-50, Huili H., Grindi B., Viau G. and Tahar L.B. Effect of Cobalt Substitution on the Structure, Electrical, and Magnetic Properties of Nanorcrystalline Ni 0.5Zn 0.5Fe 2O 4 Prepared by the Polyol Process. Ceramics International, 40: , Bhise R.B., Bhong V. and Rathod S.M. Influence of Structure and Magnetic properties of Y3+ doped Ni-Cd nanoferrite by Sol-gel Autocombustion Method. BIONANO FRONTIER, 8(3): ,2015. Page No:994