Carbon-Encapsulated Iron Carbide Nanoparticles in the Thermal Conversions of Ferrocene at High Pressures

V. Davydov (1) , A. Rakhmanina , Hassan Allouchi , Cecile Autret (2) , Patrice Limelette (2) , Viatcheslav Agafonov (2)

1 HPPI - Institute for High Pressure Physics of the RAS
2 GREMAN - UMR 7347 - GREMAN (matériaux, microélectronique, acoustique et nanotechnologies)

Pressure-temperature-induced transformations of ferrocene at 8 GPa and different temperatures up to 1000 degrees C have been studied by XRD, SEM and TEM techniques. It was shown that the thermal destruction of ferrocene at 480-600 degrees C is attended with the formation of quasi-spherical nanosized (10-30 nm) particles containing the iron carbide (Fe7C3) core and external carbon envelope from the fragments of graphene layers. Magnetic measurements indicate that the nanoparticles obtained at 8 GPa and 480-560 degrees C demonstrate a superparamagnetic behaviour at room temperature. Above 600 degrees C, the Fe7C3 nanoparticles decompose into Fe3C and graphite.

Mots clés: microscopy; XRD; Fe7C3; magnetism; nanoparticles; High pressure

Domaines: Science des matériaux [cond-mat.mtrl-sci]

V. Davydov, A. Rakhmanina, Hassan Allouchi, Cecile Autret, Patrice Limelette, et al.. Carbon-Encapsulated Iron Carbide Nanoparticles in the Thermal Conversions of Ferrocene at High Pressures. Fullerenes, Nanotubes and Carbon Nanostructures, 2012, 20 (4-7), pp.451--454. ⟨10.1080/1536383X.2012.655649⟩. ⟨hal-01716461⟩