Abstract
We report the synthesis of high magnetic moment CoFe nanoparticles via the diffusion of Co and Fe in core/shell structured Co/Fe nanoparticles. In an organic solution, Co nanoparticles were coated with a layer of Fe to form a Co/Fe core/shell structure. Further raising the solution temperature led to inter-diffusion of Co and Fe and formation of CoFe alloy nanoparticles. These nanoparticles have high saturation magnetization of up to 192 emu/g CoFe and can be further stabilized by thermal annealing at 600 °C.
![](http://media.springernature.com/lw685/springer-static/image/art%3A10.1007%2Fs12274-009-9037-4/MediaObjects/12274_2009_9037_Fig1_HTML.jpg)
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Sun, S.; Murray, C. B.; Weller, D.; Folks, L.; Moser, A. Monodisperse FePt nanoparticles and ferromagnetic FePt nanocrystal superlattices. Science 2000, 287, 1989–1992.
Lacheisserie, E. T.; Gignoux, D.; Schlenker, M. Magnetism: Materials and Spplications; Springer, 2004.
Bader, S. D. Colloquium: Opportunities in nanomagnetism. Rev. Mod. Phys. 2006, 78, 1–15.
Lu, A.-H.; Salabas, E. L.; Schüth, F. Magnetic nanoparticles: Synthesis, protection, functionalization, and application. Angew. Chem. Int. Ed. 2007, 46, 1222–1244.
Lewin, M.; Carlesso, N.; Tung, C. -H.; Tang, X. -W.; Cory, D.; Scadden, D. T.; Weissleder, R. Tat peptide-derivatized magnetic nanoparticles allow in vivo tracking and recovery of progenitor cells. Nat. Biotechnol. 2000, 22, 47–52.
Zhao, M.; Deauregard, D. A.; Loizou, L.; Davletov, B.; Brindle, K. M. Non-invasive detection of apoptosis using magnetic resonance imaging and a targeted contrast agent. Nat. Med. 2001, 7, 1241–1244.
Seo, W. S.; Lee, J. H.; Sun, X.; Suzuki, Y.; Mann, D.; Liu, Z.; Terashima, M.; Yang, P. C.; Mcconnell, M. V.; Nishimura, D. G.; Dai, H. FeCo/graphitic-shell nanocrystals as advanced magnetic-resonance-imaging and near-infrared agents. Nat. Mater. 2006, 5, 971–976.
Peng, S.; Wang, C.; Xie, J.; Sun, S. Synthesis and stabilization of monodisperse Fe nanoparticles. J. Am. Chem. Soc. 2006, 128, 10676–10677.
Xu, C.; Xie, J.; Ho, D.; Wang, C.; Kohler, N.; Walsh, E. G.; Morgan, J. R.; Chin, Y. E.; Sun, S. Au Fe3O4 dumbbell nanoparticles as dual-functional Probes. Angew. Chem. Int. Ed. 2008, 47, 173–176.
Sun, C.; Lee, J.; Zhang, M. Magnetic nanoparticles in MR imaging and drug delivery. Adv. Drug Deliv. Rev. 2008, 60, 1252–1265.
Desvaux, C.; Amiens, C.; Fejes, P.; Renaud, P.; Respaud, M.; Lecante, P.; Snoeck, E.; Chaudret, B. Multimillimetrelarge superlattices of air-stable iron-cobalt nanoparticles. Nat. Mater. 2005, 4, 750–753.
Chaubey, G. S.; Barcena, C.; Paudyal, N.; Rong, C.; Gao, J.; Sun, S.; Liu, J. P. Synthesis and stabilization of FeCo nanoparticles. J. Am. Chem. Soc. 2007, 129, 7214–7215.
Kim, J.; Rong, C.; Lee, Y.; Liu, J. P.; Sun, S. From core/shell structured FePt/FeO/MgO to ferromagnetic FePt nanoparticles. Chem. Mater. 2008, 20, 7242–7245.
Wang, C.; Peng, S.; Chan, R.; Sun, S. Synthesis of AuAg alloy nanoparticles from core/shell structured Ag/Au. Small, in press, DOI:10.1002/smll.200801169.
Hütten, A.; Sudfeld, D.; Ennen, I.; Reiss, G.; Wojczykowski, K.; Jutzi, P. Ferromagnetic FeCo nanoparticles for biotechnology. J. Mag. Mag. Mater. 2005, 293, 93–101.
Author information
Authors and Affiliations
Corresponding author
Additional information
These two authors made an equal contribution to the work.
Electronic supplementary material
Rights and permissions
Open Access This is an open access article distributed under the terms of the Creative Commons Attribution Noncommercial License ( https://creativecommons.org/licenses/by-nc/2.0 ), which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.
About this article
Cite this article
Wang, C., Peng, S., Lacroix, LM. et al. Synthesis of high magnetic moment CoFe nanoparticles via interfacial diffusion in core/shell structured Co/Fe nanoparticles. Nano Res. 2, 380–385 (2009). https://doi.org/10.1007/s12274-009-9037-4
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12274-009-9037-4