Influence of quenching on structural, size and magnetic properties of Ni0.5+XZnXCu0.5Fe2-2XO4 ferrite synthesized using ceramic route

A system of ferrites with formula Ni0.5+xZnxCu0.5Fe2-2xO4 (x=0.0,0.1,0.2,0.3,0.4,0.5) synthesized through ceramic route. As a special consideration for optimisation the material is quenched from 1137 K to 77 K by dropping it in liquid nitrogen bath in the final stage. XRD patterns present that the crystals formed are in the polycrystalline nature. The structure of ferrite is confirmed as Face Centred Cubic (FCC) phase. The particle size of the ferrite system varies from 20 nm to 40 nm and they are nano particles. Thermal study helps to infer completion of reaction of formation of ferrite. FTIR and Raman Spectroscopy measurements confirm the presence of tetrahedral and octahedral coordination of atoms in spinel structure of ferrite. However a dominating impact of defect states intruded in the structure of ferrite is visualized through FTIR and Raman Spectra. The presence of defect states is attributed to mainly to the quenching of the ferrite by a large range of fall of temperature. The existence of defect states is expected to contribute a big variation in electrical and the magnetic properties.