Synthesis of Monodisperse Nanoparticles of Cobalt and Nickel Alloys in a Template Matrix of Layered Binary Hydroxide
KONSTANTIN A. TARASOV 1, 2, VITALY P. ISUPOV1, BORIS B. BOKHONOV1 and ANATOLIY E. ERMAKOV3
1Institute of Solid State Chemistry and Mechanochemistry, Siberian Branch
of the Russian Academy of Sciences, Ul. Kutateladze 18, Novosibirsk 630128 (Russia), E-mail: tarasov@solid.nsk.su
2Novosibirsk State University, Ul. Pirogova 2, Novosibirsk 630090 (Russia)
3Institute of Metal Physics, Ural Branch of the Russian Academy of Sciences,
Ul. S. Kovalevskoi 18, Ekaterinburg 620219 (Russia)
Pages: 373-378
Abstract
The nanosized particles of Ni1 - xCox alloys encapsulated in a layered template matrix were synthesized by thermal decomposition of precursors - layered binary hydroxides [LiAl2(OH)6]2{(Ni1 - xCox(edta)} . qH2O. The morphology and the magnetic properties of the metal component were studied by X-ray phase analysis, electron microscopy (EM), and vibrational magnetometry. It was demonstrated by X-ray phase analysis that the resultant nanoparticles whose coherent scattering region (CSR) is 3-5 nm crystallize as a face-centred cubic (fcc) structure with a lattice parameter characteristic of Ni1 - xCox alloys. EM studies revealed that in going from Ni to Ni1 - xCox alloys (to x = 0.86) the particle morphology practically does not change; the particles are nearly spherical and do not range widely in size, their diameter increasing monotonously from 5.4 to 14 nm. In passing to Co (x = 100), however, the particles acquire discoid form and range widely in size, the average size being dav ~ 100nm. The results obtained demonstrated that variation of the composition of the precursor can be considered as a method of controlling the size and morphology of magnetic nanoparticles.
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