• B.KIRAN KUMAR
• Prof.Ch. Abraham Lincoln 1*.
• Prof.D.Ravinder2
• D.Ravikumar2

Magnetic-nanoparticles of MgxCo1-xFe2O4(x=0.0,0.2,0.4,0.6,0.8,1.0) have been synthesized using citrate gel auto combustion method In which citric acid is used as the complexing agent. Synthesized powders were sintered at 500oC for 4 hours in air and characterized by XRD, SEM and EDS. The X-ray diffraction study reveals that the lattice constant of cobalt ferrite decreases with the increase the magnesium content. due to the replacement of Co2+ ions with Mg2+ on octahedral site has resulted in the decrease of lattice parameters. This is because of the difference of ionic radii of Co2+,and Mg2+ which are 0.745 ´Å and 0.72 Å´ , respectively. because the decrease in mass overtakes the decrease in volume of the unit cell. From the analysis of XRD spectra particle sizes of the samples have been found upto 36nm.Scanning Electron Microscopy (SEM) studies revealed Nano nature of the samples. An elemental composition of the samples was studied by using Energy Dispersive Spectroscopy (EDS).Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy. X-ray diffraction spectra shows the single phase cubic structure (space group Fd3m) for the prepared samples. Raman spectroscopy reveals a doublet-like peak behavior in A1g and Eg modes arising due to different ionic radii of Mg/Co and Fe ions. Two prominent vibration frequencies in FTIR spectroscopy data also confirm the cubic spinel structure in the prepared samples. The dielectric constant (ε’), dielectric loss tangent (tanδ) and ac electrical conductivity (σac) of Nano crystalline Mg–Co ferrites were investigated as a function of frequency and Mg concentration. The frequency dependence of ε’, tan δ and σac is in accordance with the Maxwell–Wagner model. The effect of Mg doping on dielectric and electric properties was explained on the basis of cations distribution in the crystal structure.The magnetic parameters such as saturation magnetization, coercivity and remanence are studied with increasing the Mg-concentration in cobalt ferrite. Systematic changes in magnetic properties while going from x = 0.0 to 1.0 are discussed.

: Mg- Co Nano- Ferrites; Citrate Gel Auto Combustion Method; X-Ray Diffraction; Scanning Electron Microscope; Energy Dispersive Spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, dielectric properties, magnetic properties.

"Structural, Electrical and Magnetic Properties of Magnesium doped Cobalt Ferrite Nanoparticles Prepared by Citrate-Gel Auto Combustion Method", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 3, page no.526-541, March-2019, Available :http://www.jetir.org/papers/JETIR1903F73.pdf

"Structural, Electrical and Magnetic Properties of Magnesium doped Cobalt Ferrite Nanoparticles Prepared by Citrate-Gel Auto Combustion Method", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 3, page no. pp526-541, March-2019, Available at : http://www.jetir.org/papers/JETIR1903F73.pdf