Spinel Ferrites for Magnetic Recording Head.

Mixed-Valence Defect Ferrites : a New Family of Fine Powders and Thin Films of Spinel Ferrites

When highly divided spinel fenites become reactive enough with oxygen, to allow the oxidation of the Fe ions at low temperature and of substitute cations too, when these cations are capable of different valence states. We prepared fine particles of spinel ferrites substituted by Mn, Mo, Cu, by "chimie douce", especially from oxalate precursors and used them to reveal and to study the oxido-redu...

Ferromagnetic Properties of Zn substituted Spinel Ferrites for High Frequency Applications

This review focuses on two systems, nanocrystalline Zn substituted Co1-xZnxFe2O4 (0≤x≥1) and Ni0.4Zn0.2Mn0.4Fe2O4, were synthesized using microwave hydrothermal and auto-combustion method respectively. The synthesized powders were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), thermo-gravimetricdifferential thermal analysis (TG-DTA) and FTIR. The average parti...

Fine Powders of Co-Mn Cation Deficient Spinel Ferrites for Magneto-Optical Pigments

Enhancement of the Magnetic Properties for Co-Mn-Zn Ferrites

Aluminum substituted cobalt manganese zinc ferrite nanoparticles Co0.425Mn0.425Zn0.150AlxFe2-xO4 (from x= 0.0 to 0.15 with step 0.025) have been synthesized by chemical co-precipitation route. X-ray diffraction (XRD) and infrared spectroscopy (FTIR) revealed that the obtained powders have a single phase of cubic spinel structure. The crystallite sizes calculated from XRD data have been confirme...

Spinel ferrites as efficient magnetically reusable nanocatalysts in the solvent-free synthesis of substituted trisphenols

A series of copper and cobalt substituted nanospinel ferrites have been synthesized by the hydrothermal method. These compounds were characterized by FT-IR, XRD, EDX, SEM and VSM techniques. All of the synthesized nanospinel ferrites were found to be highly efficient and magnetically recoverable in the solvent-free synthesis of substituted 2,6-(2-hydroxybenzyl)-phenols (trisphenols). A wide ran...