Abstract
Synthesis of ‘solid solution’ and ‘core-shell’ types of well defined Co-Pt based nanoalloys smaller than 10nm have been achieved by redox transmetalation reactions. This redox transmetalation are selectively observed only if the redox potential between two metals is favorable. The composition of the magnetic alloys can also be tuned by adjusting the ratio of reactants. Annealed core-shell nanoparticles transformed into mixed nanoalloys with face centered tetragonal (fct) structures, which show large coercivity and ferromagnetism at room temperature. These nanoparticles can potentially be used as an independent single magnetic bit of tera-bit information storage. Also, this kind of redox transmetalation reaction can be utilized as a general process to synthesize various types of nanoalloys with controlled composition in a selective fashion.
Similar content being viewed by others
References
(a) D. L. Leslie-Pelecky, and R. D. Rieke, Chem. Mater. 8, 1770 (1996).
(b) A. P. Alivisatos, J. Phys. Chem. 100, 13226 (1996).
(a) M. Jacoby, C&E News, 78, 37 (2000).
(b) R. Wood, IEEE Trans. Magn. 36, 36 (2000).
(a) S. Sun, and C. B. Murray, J. Appl. Phys. 85, 4325 (1999).
(b) M. P. Pileni, Phys. Rev. B. 62, 3910 (2000).
(a) T. O. Ely, C. Pan, C. Amiens, B. Chaudret, F. Dassenoy, P. Lecante, M.-J. Casanove, A. Mosset, M. Respaud, and J. CM. Broto, J. Phys. Chem. B 104, 695 (2000).
(b) E. E. Carpenter, C. T. Seip, and C. J. O’Connor, J. Appl. Phys. 85, 5184 (1999).
(a) E. E. Carpenter, J. A. Sims, J. A. Wienmann, W. L. Zhou, and C. J. O’Connor, J. Appl. Phys. 87, 5615 (2000).
(b) S. Sun, C. B. Murray, D. Weller, L. Folks, and A. Moser, Science 287, 1989 (2000).
S. H. Liou, S. Huang, E. Klimek, R. D. Kirby, and Y. D. Yao, J. Appl. Phys. 85, 4334 (1999).
M. Thielen, S. Kirsch, A. Weinforth, A. Carl, and E. F. Wassermann, IEEE Trans. Magn. 34, 1009 (1998).
E. L. Crane, Y. You, R. G. Nuzzo, and G. S. Girolami, J. Am. Chem. Soc. 122, 3422 (2000).
S. Gu, P. Atanasova, M. J. Hampden-Smith, and T. T. Kodas, Thin Solid Films 340, 45 (1999).
(a) S. Okeya, and S. Kawaguchi, Inorganic synthesis 20, 65 (1980).
(b) W. P. Weber, G. W. Gokel, Tetrahedron Lett. 13, 1637 (1972).
J. I. Park, N. J. Kang, S. J. Oh, H. C. Ri, and J. Cheon, ChemPhysChem 3, (2002) (in press). (a) TB = 10 K and Hc = 260 Oe for 2.2 nm Co, (b) TB = 100 K and Hc = 470 Oe for 6.4 nm Co, (c) TB = 20 K and Hc = 370 Oe for 4.0 nm Co nanoparticles, respectively.
X-ray Powder Diffraction Patterns (“International Centre for Diffraction Data”, Newtown Square, PA) (1996).
(a) G. Schmid, A. Lehnert, J. O. Malm, J. O. Bovin, Angew. Chem. Int. Ed. Engl. 30, 874 (1991).
(b) G. Schmid, H. West, H. Mehles, A. Lehnert, Inorg. Chem. 36, 891 (1997).
(c) T. Wang, N. Toshima, J. Phys. Chem. B 101, 5301 (1997).
J. I. Park, J. Cheon, J. Am. Chem. Soc. 123, 5743 (2001)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Park, JI., Kang, aJ., Lee, SM. et al. Enhanced Magnetic Transition of Core-Shell Cobalt-Platinum Nanoalloys. MRS Online Proceedings Library 721, 58 (2002). https://doi.org/10.1557/PROC-721-E5.8
Published:
DOI: https://doi.org/10.1557/PROC-721-E5.8