Abstract:
Spinel ferrites are the technologically important materials whose application ranges from the environmental, bio-medical to the smart devices. The properties of the ferrite can be tuned by varying the particle size of the different metal ion substituted in the core of the ferrite. In the present studies, we have successfully prepared sparingly investigated Ni sub(0.7-x) Mn sub(x) Zn sub(0.3) Fe sub(2) O sub(4) (x = 0.1-0.6) ferrite series by precursor combustion method using nickel-manganese-zinc-iron fumarato-hydrazinate as precursor. These metal fumarato-hydrazinate precursors burn auto-catalytically, once ignited with a burning splinter, to form metal ferrites. The detailed study of these precursors was carried out using TG-DTA, IR, CHN analysis, isothermal mass loss and total mass loss studies. The experimental hydrazine content as well as contents of C, H, N, Ni, Mn, Zn and Fe of the precursors matched exactly with the theoretical values. The thermal analysis of the precursors suggest mainly two major steps decomposition. The XRD patterns and the IR spectra of the ferrites obtained by burning these precursors confirmed the single-phase cubic nature of these ferrites. The resistivity studies indicate decrease in resistivity with increase in Mn sup(2+) content of the ferrites. The Curie temperature also shows the same trend.
