Technology of Fabrication and Morphology of Multiwalled Carbon Nanotubes on Co-Ni/MgO Catalysts by Thermal CVD
Multiwalled carbon nanotubes (MWNTs) were fabricated by thermal chemical vapor deposition (CVD) using monometallic and bimetallic Co and Ni on MgO as the catalyst. The mixture of H2/C2H2 gas was used as carbon source. The prepared CNTs have different sizes/shapes and morphologies with minimal formation of carbon particles. The maximum yield of CNTs was obtained with 50% Co catalyst at 600 oC. The morphology of the CNTs with 50% Co loading generates curved structure while 50% Ni results in the formation of linear structure with aligned graphene walls. Intensity ratio of D and G-peaks (ID/IG) was measured from Raman spectra. Scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) was done for the structural analysis of the prepared MWNTs.
H. J. Ryu et al., "Technology of Fabrication and Morphology of Multiwalled Carbon Nanotubes on Co-Ni/MgO Catalysts by Thermal CVD", Journal of Nano Research, Vol. 4, pp. 45-64, 2008