Interactions and hysteresis behaviour of Fe/SiO2 nanocomposites

Role of the poly-dispersity and the dipolar interaction in magnetic nanoparticle systems: Monte Carlo study

“…Now, we focus on the variation of coercive field along with the concentration. Simulated and experimental results [5][6][7][8][9]19,29,30] showed that the increase of coercivity in the low-concentration region, therefore, the curves expresses a peak at the threshold value of concentration. First, Kechrakos and Trohidou [5] found the maximum peak of the magnetic coercivity vs. concentration curve in the purely dipolar case (K u = 0) even at very low temperature.…”

“…In our case, the position of particles is frozen, the bond axis does not change leading to the positive contribution of the anisotropic term along the bond axes of dipolar interaction [28]. In case particles align to form chains along the bond axis, these structures will behave as single particles having the high shape anisotropy [17,29,30]. Fig.…”

A facile and novel approach to magnetic Fe@SiO2and FeSi2@SiO2nanoparticles

“…8 Due to their unique magnetic properties various methods for the preparation of SiO 2 -coated metallic nanoparticles have been developed in the last few years. Traditionally, these materials have been prepared by using methods such as high-energy ball milling, 9 wet chemistry, 1 arc discharge, 10 and pyrolysis of polysiloxane block copolymers. 11 Furthermore, transition metal silicides as a class of materials have recently been paid attention due to their special physical and chemical properties.…”

Synthesis and magnetic properties of Fe/SiO2 nanocomposites prepared by a sol–gel method combined with hydrogen reduction

“…The protective shell on the surface of the particle may also prevent interactions between neighboring magnetic particles as well as grain growth and agglomeration during heat treatment. SiO 2 -coated Fe nanoparticles have been prepared by high-energy ball milling [5] and wet chemical method [6] before, but their sizes are too large, and the coating process is hard to control. In this paper, we report a simple sol-gel method combined with hydrogen reduction that is effective and controllable to coat Fe nanoparticles with silica shells.…”