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Self-organized vertically aligned or entangled randomly-oriented carbon nanotubes films filled with ferromagnetic Fe-based phases have recently attracted a great attention for numerous applications as potential electrodes. However the large difference between their synthesis –i) methods, -ii) parameters or –iii) the specific hydrocarbons-requirement have posed many challenges in the growth-selection of one of these film-morphologies. Another important issue is the brittleness of the first type of films which is generally due to low intimate contacts between each carbon nanotube comprised in the vertically aligned films and limits their direct implementation into applications. We propose an advanced low-flow rate chemical vapour deposition approach which allows the selection of either a free-standing flexible film comprising vertically aligned carbon nanotubes filled with large quantities of Fe 3 C particles or a free-standing flexible buckypaper comprising entangled randomly-oriented carbon nanotubes films partially filled with Fe 3 C through the simple control of the evaporation temperature of the used precursors consisting of large quantities of ferrocene and very low concentrations of dichlorobenzene. The morphological, cross sectional and structural properties of the obtained nanostructures are investigated. [ABSTRACT FROM AUTHOR]

FePd and CoPd tetragonal ferromagnetic nanoparticles have recently attracted a great attention due to their large magneto-crystalline anisotropy of ∼10 8 erg/cm 3 ideal for fabrication of magnetic-arrays with giant-coercivities. However, no studies are reported on the fabrication of these alloys inside carbon nanotubes. Here we reveal the synthesis of the FePd 3 –Fe 0.037 Pd 0.963 –Fe 3 C inside carbon nanotubes by chemical vapor deposition of large quantities of ferrocene with low quantities of dichloro-cyclooctadiene-palladium and its transformation to Fe 0.438 Pd 0.561 through annealing. Instead, planar graphitic structures with embedded FePd 3 –Fe 0.037 Pd 0.963 or CoPd/CoPd 2 particles are found when large quantities of dichloro-cyclooctadiene-palladium are pyrolyzed with low quantities ferrocene or cobaltocene. [ABSTRACT FROM AUTHOR]