Effect Of Catalyst Concentration On The Synthesis Of MWCNT By Single Step Pyrolysis
B. V. Mohan Kumar, Rajesh Thomas, Ambily Mathew, G. Mohan Rao, D. Mangalaraj, N. Ponpandian, C. Viswanathan
Keywords: Multiwall carbon nanotubes; single step pyrolysis; ferrocene; xylene.
Multiwall carbon nanotubes (MWCNT) are synthesised by cost effective method of pyrolysing xylene (as hydrocarbon, precursor) in the presence of ferrocene (as catalyst) at 750oC. The so obtained MWCNTs has a length ranging from 90 µm to 300 µm and diameter ranging from 20 nm to 200 nm depending on the amount of ferrocene added to the xylene for the synthesis. The diameter of the MWCNT’s increased with the increase in ferrocene content in the precursor solution. Bigger agglomerates of iron particle lead to the growth of larger diameter MWCNTs. These MWCNTs with higher concentration of iron nanoparticles in it are useful for catalytic applications. X-ray diffraction (XRD) of the as-synthesised MWCNTs showed a graphitic-like peak (002). Field emission scanning electron microscope (FESEM) is utilized for its morphological analysis, Raman analysis showed the presence of D band (~1350 cm-1) and G band (~1580 cm-1) indicating high crystalline graphitic layers. Fourier transform infrared (FTIR) studies in the transmission mode were carried out in the range 400-4000 cm-1 (peaks at 1386, 1639, 2363, 3434, 3747 cm-1 etc.,) for bond stretching analysis. All the characterization processes were carried out before and after purification process. The MWCNT’s diameter and their distribution are studied with the help of ImageJ software using the FESEM micrographs.