Interactions of electron beam with spring-like MWNT's synthesized by CVD method.

Multi-walled carbon nanotubes (MWNT's) are prepared by using a thermal catalytic-chemical vapor deposition (CVD) using acetylene gas as the precursor and powdered nickel as catalyst. Argon gas is used as a carrier gas and the growth characteristics of MWCNT's were controlled using flow rate, Ar/C2H2 ratio and temperature. The interaction of the electron beam with MWNT's is investigated using a scanning electron microscope in the regime of 5 to 30 kV. The structural details of the MWCNT's were studied using X-ray diffraction and FTIR spectroscopic analysis. Interestingly, the nanotubes have grown as helical/spiral coils with multi-terminal junctions as Y or H were observed. The FTIR analysis showed C-C, C=C, C-H bending and stretching modes at 1100, 1531, 1593, 924, 2924 cm^-1 confirming the presence of multiwalled carbon nanotubes. Further, the XRD analysis showed sharp reflections of (002), (101) and (110) planes. The electron beam interaction with multiwalled carbon nanotubes showed the axial joining of tubes. The carbon atoms found to have displaced from the surface of MWCNT's create vacancies and disordered rings of carbon structures. These disordered rings of two different nanotubes joined together as they bend due to potential field. [ABSTRACT FROM AUTHOR]