A significant improvement ~220%! is reported in the low voltage ~2000 V! aging characteristics under cathodoluminescence ~CL! excitation for ZnS phosphors coated with 1.0 wt % SiO2 by the sol-gel technique. The formation of nanoscale uniform coating was confirmed by structural analysis. An improvement in chemical and thermal stability was also confirmed by chemical etching and heat-treatment of...

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...

Articles you may be interested in Dielectric relaxations and alternating current conductivity in manganese substituted cobalt ferrite Impedance spectroscopy study of strontium modified lead zirconate titanate ceramics Dielectric and magnetic properties of sol-gel-derived lead iron niobate ceramics Gadolinium (Gd) substituted cobalt ferrites (CoFe 2Àx Gd x O 4 , referred to CFGO) with variable G...

Bimagnetic monodisperse CoFe₂O₄/Fe₃O₄ core/shell nanoparticles have been prepared by solution evaporation route. To demonstrate preferential coating of iron oxide onto the surface of ferrite nanoparticles X-ray diffraction (XRD), High resolution transmission electron microscope (HR-TEM) and Raman spectroscopy have been performed. XRD analysis using Rietveld refinement technique confirms single ...

The magnetic properties of nano-crystalline CoMxFe2 xO4 (where M=Gd and Pr and x 1⁄4 0; 0.1 and 0.2) powders prepared by a citrate precursor technique have been studied by using vibrating sample magnetometer (VSM). The crystallite sizes of the materials were varied by altering the synthetic conditions and are within the range of a minimum of 6.8 nm and a maximum of 87.5 nm. The materials were c...

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...

The square arrays are fabricated by e-beam lithography on polycrystalline Co sputtered on glass substrates. First, a continuous layer, 1000 nm thick, of polycrystalline Co is grown. This thickness guarantees optical opacity for the light used in the experiments, a 632.8 nm wavelength 1.5 mW laser. Secondly, the continuous Co layer is locally etched (all the way through to the glass substrate) t...

Recent advances in the synthesis of various magnetic nanoparticles using colloidal chemical approaches are reviewed. Typically, these approaches involve either rapid injection of reagents into hot surfactant solution followed by aging at high temperature, or the mixing of reagents at a low temperature and slow heating under controlled conditions. Spherical cobalt nanoparticles with various crys...

Cobalt-doped magnetite (CoxFe3 -xO4) nanoparticles have been produced through the microbial reduction of cobalt-iron oxyhydroxide by the bacterium Geobacter sulfurreducens. The materials produced, as measured by superconducting quantum interference device magnetometry, X-ray magnetic circular dichroism, Mössbauer spectroscopy, etc., show dramatic increases in coercivity with increasing cobalt c...