Characterization Of Nano-structured Magnesiumchromium ferrites Synthesized By Citrate-gel auto Combustion Method

¹Department of Chemistry, Jayaprakash Narayan College of Engineering, Mahabubnagar 509001, Andhra Pradesh, India

²Department of Physics, Nizam College, Basheerbagh Osmania University, Hyderabad 500001, Andhra Pradesh, India

³Department of Chemistry, Osmania University, Hyderabad 500007, Andhra Pradesh, India

Adv. Mater. Lett., 2013, 4 (12), pp 910-916

DOI: 10.5185/amlett.2013.5479

Publication Date (Web): Nov 24, 2013

Copyright © IAAM-VBRI Press

E-mail: ravindergupta28@rediffmail.com, raghasudha_m@yahoo.co.in

Abstract

Nano-ferrites of the composition Mg Cr_x Fe_2-xO₄ (where x=0.0, 0.1, 0.3, 0.5, 0.7, 0.9 and 1.0) were synthesized at a very low temperature (180°C) by Citrate-gel auto combustion method. The as synthesized powders were sintered at 500⁰C for four hours in an air and were characterized by X-ray diffraction (XRD) which confirmed the formation of cubic spinel structure of ferrites. The crystallite size was in the range of 7 to 23nm for different compositions with the significant decrease of ~16nm in response to the increase in Cr substitution. Such low nano sized ferrites are desirable for variety of applications like, in magnetic data storage and in targeted drug delivery, etc. Morphological studies by Scanning Electron Microscopy (SEM) revealed formation of largely agglomerated, well defined nano particles of the sample. Elemental composition characterizations of the prepared samples were performed by Energy Dispersive Spectroscopy (EDS) which shows the presence of Mg, Cr, Fe and O without precipitating cations. The FTIR spectral studies at room temperature in the range of 400 to 800cm-1 showed two strong absorption bands. The high frequency band (ν1) around 600 cm^-1 is attributed to the intrinsic vibrations of tetrahedral complexes and the low frequency band (ν2) around 400 cm^-1 is due to octahedral complexes. The spectra showed the characteristic peaks of ferrite sample. The observed results can be explained on the basis of composition and crystal size.

Keywords

Nano-ferrites, citrate-gel auto combustion, X-ray diffraction, SEM, EDS, FTIR.