JOURNAL OF APPLIED PHYSICS, cilt.107, sa.9, 2010 (SCI-Expanded)
In this work, the results of synthesis of core-shell NiFe2O4 nanoparticles and influence of silica coating on the magnetic properties of nanoparticles are presented. Spherical NiFe2O4 nanoparticles were prepared via a normal micelles process. NiFe2O4 nanoparticles homogeneously coated with SiO2 of various shell thickness were synthesized by reverse microemulsion. The interparticle spacing was varied by changing the amount of added tetraethylorthosilicate. The microstructures and morphologies of these nanoparticles were studied by x-ray diffraction and transmission electron microscopy techniques. The magnetic parameters such as saturation magnetizations, blocking temperatures, and magnetic anisotropies have been calculated from dc magnetization and ac susceptibility measurements. (C) 2010 American Institute of Physics. [doi:10.1063/1.3359426]