Magnetic properties of CoFe2O4 nanoparticle synthesized by salt-assisted sol-gel auto-combustion method

CoFe2O4 nanoparticle was synthesized by sol-gel auto-combustion of citrate-nitrate precursors in presence of KCl as capping agent to reduce the particle size. Transmission electron microscopy (TEM) and x-ray diffraction (XRD) analysis indicated that the particle size and crystallite size of CoFe2O4 was significantly reduced by incorporation of KCl during combustion. Phase identification by XRD as well as electron diffraction using TEM revealed that the sample prepared by salt-assisted combustion route is a single phase CoFe2O4 without any impurity. It was found that the magnetic properties of the sample synthesized by salt-assisted combustion were significantly different to those of the sample synthesized by conventional route, which is discussed based on the Mossbauer spectroscopy and the temperature dependent magnetization analyses. Cation distribution measurement by analyzing the XRD patterns as well as Mossbauer spectra revealed that the inversion degree of spinel structure is increased by incorporation of the salt in combustion synthesis of the CoFe2O4.