Physico-chemical regularities of obtaining highly dispersed magnetite by the method of chemical condensation

An experimental study of the dynamic properties of nanoparticle colloids with identical magnetization but different particle size

“…In Ref. [10] it is shown that the rate of magnetite formation depends on the pH value of the reacting medium, the concentration of reagents, the nature of the precipitator and the temperature of synthesis. [12]) and therefore it has not been of much commercially concern in manufacturing magnetic fluids, with respect to their saturation magnetization.…”

“…The possibility of the presence of "miscellaneous particles" in the samples [10,13], which could influence the value of H A was also investigated by means of X-ray analysis. This analysis has confirmed the absence of any significant amount of other iron oxides in the samples thereby indicating that, in this case, the value of H A was not influenced by the presence of other particles types.…”

Synthesis and Potential Adsorption of Fe3O4@C Core-Shell Nanoparticles for to Removal of Pollutants in Aqueous Solutions: A Brief Review.

“…In contrast, coprecipitation processes occur when there is a reaction between two or more hydro soluble salts and the formation of at least one insoluble salt that precipitates [57,71]. Thus, in the hydrothermal coprecipitation process there is the combination of these two methods for the formation of both the core, by the precipitation of Fe 3 O 4 , and the carbon shell, by the hydrothermal process.…”

“…The coprecipitation process occurs in two stages: first, a fast nucleation period, which happens when the concentration of the reagent reaches critic super saturation; afterwards, there is the stage for the slow growth of the cores by the diffusion of solutes on the crystal's surface [57,65,71]. The formation of the shell in the core occurs through a heterogeneous nucleation process.…”

“…During the synthesis of nanoparticles, factors such as pH, temperature, the nature of salts (perchlorides, chlorides, sulphates and nitrates) and the ratio of Fe 2+ /Fe 3+ concentration can be adjusted to control format, size, magnetic characteristics and surface properties [57,65,71,72]. Furthermore, the use of surfactant agents can help control the dispersion of the magnetic nanoparticles, reducing the formation of agglomerates through the stabilization of attractive and repulsive forces [41,65].…”