E. G. Gerasimov, P. B. Terentev, N. N. Shchegoleva, N. V. Mushnikov, B. Campbell, A. N.Pirogov, Y. N. Scryabin, А. Е. Teplykh, S. G. Bogdanov, V. E. Fedorov, N. G. Naumov, A. P. Vokhmyanin, V. V. Bobrovskiy

STRUCTURAL STATE OF NANOCOMPOSITES BASED ON HIGHLY EXFOLIATED GRAPHITE AND 3d-TRANSITION METALS

The structural state and magnetic properties of nanocomposites formed by exfoliated graphite and 3d-transition metal (Co or Ni) particles have been studied. The exfoliated graphite was synthesized by thermal decomposition of the intercalated graphite C2Fx(BrF3). The thus synthesized exfoliated graphite is multilayer graphene. The salt CoCl2×6H2O (or NiCl2×6H2O) was added to the graphene, and the mixture was agitated by a stirrer for half an hour and then heated in a hydrogen flow. The microstructure of the nanocomposites represents separated practically spherical inclusions of Co (or Ni) nanoparticles into a multilayer graphene matrix. The X-ray diffraction patterns of the nanocomposites with Co particles testify to their two-phase state at 293 K: they crystallize in low-temperature hexagonal and high-temperature cubic phases. At 78 K and 293 K, the magnetization curves of the nanocomposites, which are measured in pulsed magnetic fields of up to 100 kOe, look typically of ferromagnets.

Acknowledgment: This research was carried out within the SA of FASO of Russia (themes “Magnet” No. 0120146332 and “Flux” No. 01201463334).

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