Preparation and Characterization of Nanostructured Ferrite Materials by a Nitrate-Citrate Self-Combustion Sol–Gel Synthesis
New chemical synthesis procedure for the preparation of nickel zinc doped W-type hexagonal barium ferrite and aluminium doped yttrium-iron garnet nanoparticles has been developed, using the nitrate-citrate sol-gel auto-combustion method (NCSAM). The crystalline phase attributes, microstructure, morphology, specific surface area, Curie temperature (TC), permeability, thermal behavior of the as-burnt phase and the heat treated powders were characterized using XRD, SEM, FT-IR, BET, TG-DTA and AC magnetic permeability with frequency shift. In the case of the hexaferrite, the pure W-type ferrite phase is formed during 4 hour annealing at a temperature of 1200 °C, the garnet phase is formed at a lower temperature i.e. 1000 °C. Furthermore it has been confirmed, that the AC magnetic permeabilities of the garnet materials are strongly depending on the chemical composition.
P.J. Szabó, T. Réti, T. Czigány
L. Trif et al., "Preparation and Characterization of Nanostructured Ferrite Materials by a Nitrate-Citrate Self-Combustion Sol–Gel Synthesis", Materials Science Forum, Vol. 589, pp. 167-172, 2008