Magnetic fine particles of Fe and Co encapsulated by carbon layers

Synthesis of carbon-encapsulated iron nanoparticles via solid state reduction of iron oxide nanoparticles

“…In each case, the reflection for the bcc Fe is the strongest, which shows that the content of this phase significantly exceeds the fraction of still present iron oxides. This findings are in disagreement with previous reports [18,19], showing that the annealing temperature of 1000 1C and reaction time 2 h are sufficient to totally reduce all iron oxides to the pure metal phase. The presence of iron oxides is also reflected by the mass of collected products.…”

“…Contrary to the previous literature reports [18,19], three distinct carbon materials were used as reductants, i.e. carbon black, hollow carbon nanoparticles and ultra-fine graphite powder.…”

“…The samples synthesized from carbon black and graphite contain large non-uniform ''glassy'' objects, which can be ascribed to the reduced Fe. The [18,19]. TEM studies were conducted to visualize the morphology of the Fe-containing crystallites appearing in XRD patterns of the purified products.…”

“…Another routes involve two-step processes in which the carbon coatings were deposited onto previously prepared metal nanoparticles with specified diameters [16,17]. The present work is motivated by recent papers demonstrating that carbon-encapsulated iron nanoparticles (CEINs) can be effectively formed by a very simple process-carbothermal reduction (900-1000 1C) of iron oxide nanoparticles by carbon black [18,19]. The both precursors are cheap and environmentally friendly.…”

Fe fine particles encapsulated by titanium oxides with high magnetization for biomedical application

“…We have developed a simple procedure to fabricate Fe and Co fine particles encapsulated by C layers [10,11]. Developing this procedure, synthesis of Fe fine particles encapsulated not by C, but by titanium oxide has been tried because titanium oxides are known to show chemical stability and biocompatibility [12].…”