Magnetic metal nanopartides

The magnetic metals were also prepared by a method [25] based on the rapid expansion of supercritical fluid solutions (RESS) coupled with chemical reduction to produce nickel, cobalt, iron, and iron oxide nanopartides of reasonably narrow size distribution. Under the protection of a polymer stabilization agent, the largely amorphous metal nanopartides form stable suspensions in room-temperature solvents. 

The monolayers described so far have all been grown by self-assembly processes, where ligand-stabilized metal nanopartides are deposited on innocent surfaces from solution, followed by a more or less rapid evaporation of the solvent. Depending on the concentration and other experimental conditions, those procedures may occasionally also result in multilayers, or even in small 3-D microcrystals. Self-assembly processes can, however, also be supported by chemical, electrochemical, magnetic, or mechanical effects some examples of these are provided in the following subsections. 

Abu-Reziq, R., Alper, H., Wang, D.S. and Post, M.L. (2006) Metal supported on dendronized magnetic nanopartides highly selective hydroformylation catalysts. Journal of the American Chemical Society, 128 (15), 5279-5282. 

Other Metal Magnetic Nanopartides Synthesized by Methods of Colloidal Chemistry In the previous sections, the coUoidal synthesis of Co and CoPts nanocrystals and the great potential of an organometallic approach in the preparation of high-quality magnetic nanoparticles have been discussed. Yet, these synthetic... 

The preparation of core-shell -type magnetic nanopartides was reported [92,93] as a two-step synthesis in which nanopartides of one metal served as the seeds for growth of the shell from another metal. Thus, the reduction of platinum salts in the presence of Co nanopartides would allow the preparation of air-stable CocorePtsheii nanopartides [92]. The thermal decomposition of cobalt carbonyl in the presence of silver salt led to the formation of AgcoreCOgheii nanopartides [93]. The syntheses of these multicomponent magnetic nanostructures are discussed in Section 3.3.2.4. 

Several recent studies sought to adsorb heavy metals onto magnetic nanoparticles. For example, the removal and recovery of Cr(VI) has been achieved by synthesized maghemite (Y-Fe203) nanopartides, and it is proved that Cr(VI) adsorption capadty of nanoscale maghemite compared favorably with other... 

Preparation of poly (1-vinylimidazole)-grafted magnetic nanopartides and their application for removal of metal ions. Chemistry of Materials, 16,1977-83. 

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