Synthesis and Characterization of CoFe_2-_xY_xO_4 (x= 0.05-0.2) by Auto Combustion Method

摘要

The Yttrium doped Co ferrite nanoparticles were synthesized by Auto combustion route. The XRD of the synthesized ferrites revealed cubic spinel phase formation whereas their Neutron diffraction studies confirmed the existence of secondary phase formation. The average lattice parameters calculated was 8.384? and the estimated particle size was around 20 nm. SEM results revealed exaggerated grain growth with agglomeration of grains and non uniform grain structure. Resistivity measured was found to increase with increase in Yttrium content. Dielectric dispersion curve revealed Maxwell-Wagner type of polarization asserting Koop's model in these particular compositions. The two important parameters namely retentivity and coercivity show random variation with change in Y~(3+) ion concentration. It is observed that x=0.15 compositions has almost square wave loop type characteristic suggesting its application in memory devices.