Growth of carbon nanotubes decorated with Fe nanoparticles encapsulated by graphitic layers on diamond film on cemented carbide substrate

• MWCNTs decorated with Fe-NPs have been obtained on diamond film by the pyrolysis of FePC at 850 °C.
• The results show that all MWCNTs randomly lay down and are curvy on the diamond film.
• High density of structural defects in carbon nanotubes are formed in the pyrolysis process at low temperature.
• The Fe-NPs are encapsulated with graphitic layers and anchored on the MWCNT surface.
• The MWCNT layer is directly bonded to the diamond layer.

MWCNTs decorated with Fe-NPs have been obtained on diamond film on cemented carbide substrate (MWCNTs/Fe-NPs/diamond/cemented carbide) by the pyrolysis of FePC at 850 °C. The microstructure and elemental compositions of the prepared samples are studied with SEM, TEM and EDS. MWCNTs/Fe-NPs/diamond/cemented carbide is also analyzed by Raman spectroscopy. The results show that all MWCNTs randomly lay down and are curvy on the diamond film with short lengths. High density of structural defects in carbon nanotubes are formed in the pyrolysis process at a relative low temperature. The Fe-NPs are encapsulated with graphitic layers and anchored on the MWCNT surface. The growth of these MWCNT/Fe-NPs composites is well explained using the concepts of the vapor–liquid–solid (VLS) model.