Mossbauer study of iron-containing carbon nanotubes

Marco JF, Gancedo JR, Hernando A, Crespo P, Prados C, Gonzalez JM, Grobert N, Terrones M, Walton DRM, Kroto HW

Fe-57 transmission Mossbauer at temperatures between 18 and 298 K and magnetic measurements have been used to characterize Fe-filled carbon nanotubes which were prepared by pyrolisis of Ferrocene + C-60 at atmospheric pressure under an Ar atmosphere at 1050 degreesC. The Mossbauer data have shown that the Fe phases encapsulated within the carbon nanotubes are alpha-Fe, Fe3C and gamma-Fe. The magnetic results are compatible with the Mossbauer data. Taken together the results allow us to propose a simple picture of the distribution of iron phases within the carbon nanotubes which would consist of an alpha-Fe core surrounded by an gamma-Fe shell, finally covered by an Fe3C layer.

Keywords:

CARBON NANOTUBES

,

PARTICLES

,

alpha-Fe

,

coercive field

,

Fe nanowires

,

gamma-Fe

,

Mossbauer spectroscopy