Based on a self-assembly strategy, spherical mesoporous cobalt and nickel ferrite nanocrystal clusters with a large surface area and narrow size distribution were successfully synthesized for the first time via a template-free solvothermal process in ethylene glycol and subsequent heat treatment. In this work, the mesopores in the ferrite clusters were derived mainly from interior voids between...

Well-defined CoFe2O4 nanoparticles embedded in amorphous SiO2 matrix have been synthesized by sol-gel method, characterized and investigated by Mössbauer spectroscopy and magnetic measurements. The mean particle size was found to increase from 3 to 15 nm by varying the temperature of a subsequent annealing from 800 to 1100 ◦C. The composites exhibited superparamagnetic behavior with the blockin...

The enhanced interest of the researchers in nanoobjects is due to the discovery of unusual physical and chemical properties of these objects, which is related to manifestation of so-called ‘quantum size effects‘. These arise in the case where the size of the system is commensurable with the de-Brogli wavelengths of the electrons, phonons or excitons propagating in them.A key reason for the chan...

Present work aims to investigate effect of 100 MeV oxygen ion irradiation on the vibrational modes of zinc ferrite nanoparticles. Nanosize zinc ferrite systems of different crystallite size ranging from 12-62 nm were irradiated at the fluence of 1×10(13) and 5×10(13) ions/cm(2). High resolution transmission electron micrograph study indicates the structural disorder induced by ion irradiation. ...

Superparamagnetic single phase zinc ferrite nanoparticles have been prepared by coprecipitation method at 20 °C without any subsequent calcination. The composition, crystallite size, microstructure and magnetic properties of the prepared nanoparticles were investigated using X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscope (TEM)...

Ferromagnetic nanomaterials are of particular interest, because at nanoscale a crystallite can exhibit a single magnetic domain. These nanomaterials therefore exhibit different magnetic properties as compared to bulk. Recently, barium ferrite has gained importance due to its potential use in magnetic recording and in microwave devices. Barium ferrite nanoparticles are prepared by the citrate pr...

Introduction Magnetic oxide nanomaterials, including iron oxide (Fe3O4 and γ-Fe2O3), spinel ferrites (MFe2O4; M=Mn, Zn, Cr, Ni, or Co) and hexagonal ferrite (MFe12O19, M=Ba and Sr) are attracting much attention due to their wide application potentials in advanced magnets, electronic devices, information storage, magnetic resonance imaging (MRI), and drug-delivery technology [1-6]. Hence, the sy...

cobalt ferrite is an important magnetic material due to their large magneto-crystalline anisotropy, high cohercivity, moderate saturation magnetization and chemical stability.in this study, cobalt ferrites nanoparticles have been synthesized by the co-precipitation method and a new microemulsion route. we examined the cation occupancy in the spinel structure based on the “rietveld with energies...

magnetic nanoparticles are the good choice for using in mri as the contrast agent. iron oxide particles such as magnetite (fe3o4) or its oxidized form maghemite (γ-fe2o3) are the most commonly employed in biomedical applications. in this study, we synthesized and optimized the preparation of chitosan manganese-ferrite nanoparticles (cmn-fe nps) and evaluated its ability for the mice macrophage ...