Effects of Substrates on the Growth Mode of Carbon Fibers
In this study, we have synthesized vapor grown carbon nanofibers on three types of substrates: graphite, ceramic, and titanium dioxide nanotube array, which were coated with copper salt catalyst precursors. Copper salt and acetylene were used as catalyst precursor and carbon source, respectively. The morphology and structure of the as-obtained product were analyzed using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and X-ray powder diffraction (XRD). Experimental results demonstrate that the morphology of carbon fibers synthesized on graphite substrate is similar to that on the ceramic. However, carbon fibers with small diameters of about 20-40 nm were synthesized on the titanium dioxide nanotube arrays. This means, growth substrate plays important roles in the formation of catalyst particles and thereby affects the growth mode of carbon nanofibers.