Research Of Aligned Carbon Nanofibers Synthesized On Metal Substrate With Copper Nanoparticles

In view of a very important role in the coming age of nanotechnology, carbon nanofibers (CNFs) have been attracting more and more attentions of researchers worldwide since its discovery. Carbon nanofiber is a new type of nano-materials, which diameter is between carbon nanotube and carbon fiber produced by chemical vapor deposition (CVD). So CNFs not only have all characters of common carbon fibers, but also have high aspect ratio, unique mechanical, electrical and thermal properties. Many potential applications have been proposed for CNFs, including double lay capacitor electrode, anode of lithium ion battery, structure strengthen materials, and probes of electro-chemical based on these unique properties.In this paper, carbon nanofibers were synthesized through chemical vapor deposition of acetylene with different catalysts on different metal substrates at low temperature. The influences of reaction temperature, reaction time and loading time on the morphology of carbon nanofibers were investigated. The morphologies and structures of carbon nanofibers were studied by SEM, XRD, and IR etc. The growth mechanism of carbon nanofibers was also discussed.The result showed that there were three different morphologies of carbon nanofibers were formed, including carbon nanofibers arrays, helical carbon nanofibers and straight carbon nanofibers in the products.Carbon nanofiber arrays were synthesized both with copper sol as catalyst precursors on copper substrate and with copper tartrate as catalyst precursors on iron substrate. Straight carbon nanofibers were synthesized with copper sol as catalyst precursors loaded on iron and aluminum substrates respectively. Straight and helical carbon nanofibers were produced when using copper tartrate as catalyst precursors which loaded both on iron and aluminum substrates.Further studies revealed that lengths of carbon nanofibers increased by prolonging the reaction time without any changes of other conditions; meanwhile there were no obvious changes in diameters. Lower heating rate would mount up the length of carbon nanofibers. The duration of catalyst precursors loaded on metal substrates played a central role on the morphology of carbon nanofibers. The more it sustained, the more aligned CNFs would obtained. The influences of temperature on the morphology of carbon nanofibers varied from different metal substrates which loaded with different catalysts precursors.In addition, it is pointed that copper nanoparticles catalyze the synthesis of carbon nanofibers through the chemical vapor deposition of acetylene when using both copper tartrate and copper sol as catalysts.