MAGNETIC PROPERTIES OF NANOCRYSTALLINE NICOZN FERRITE SYNTHESIZED BY CITRATE-NITRATE COMBUSTION METHOD

Mixed Nano particles of Ni Co Zn Fe O , ferrite material were prepared 0.57 0.03 0.35 2.05 4by a chemical combustion route and powder was sintered at temperature 9500C. This method involves the addition of aqueous nickel nitrate, cobalt nitrate, zinc nitrate, ferric nitrate as oxidizing agent and fuel citric acid as a reducing agent to form a homogenous redox mixture. The structure and morphology of samples were studied using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The crystallite size has been estimated by the Debye – Scherrer formula using the full width at half maximum of the line broadening of the (311) reflection and it is found to be around 66nm. The SEM was used to analyze the grain size distribution in ferrite. The SEM picture shows agglomerated grains with different shapes and sizes. The ferrite powder was pressed in the form of torroids and permeability spectra were analyzed. The initial permeability (μi) was found to increases and loss factor decreases as frequency increases. From thermal variation of loss factor, it is observed that because of low loss factor, the ferrite must be operated below Curie temperature.