Abstract
Herein, we report the in situ synthesis of multi wall carbon nanotubes (MWCNTs) in addition to nanofibers on the surface of an acid etched commercial stainless cylinder in a catalytic chemical vapor deposition reactor using ethanol as a carbon source. The MWCNTs and nanofibers mixture was characterized via SEM, EDS, TEM and XRD techniques. SEM imaging showed randomly oriented thick carbon nanotubes (CNTs) of different shapes and sizes accompanied by carboneous material. EDX analysis showed carbon content of approximate to 97%. The TEM images showed thick (MWCNTs) in the range of 20-70nm with approximate to 0.4nm distance between the concentric tubes forming the walls. Furthermore, the SEM and TEM reflections exhibited carbon nano-fibers of about 300nm diameters. The XRD confirmed the characteristic peaks of the graphite at 2? value of 26 degrees and 43 degrees. The structure of the nanotubes was correlated to the surface morphology of the steel substrate. The simultaneous formation of CNTs and nanofiber on stainless steel without a catalyst was successfully accomplished. The growth of nanotubes and nanofibers almost takes the same approaches with the difference in the size of nanoparticles and its orientation was detrimental in the type of product. Smaller nanopraticles entering longitudinally are observed inside the nanotubes, whereas transversely oriented large nanoparticles are observed in case of nanofibers. An excellent perceptive of nanotubes and nanofibers growth on metal surface is perhaps an excellent approach to explore the mass production of such carbon nanostructures, control conditions and surface in quest to tailor well-designed structures. These results give a clue to the possibility of using commercial stainless steel as a substrate and catalyst for versatile route preparation of multi-wall CNTs.