Preparation of Large Carbon Nanofibers on a Stainless Steel Surface and Elucidation of their Growth Mechanisms

Abstract

Abstract In this work different shapes of carbon nanofibers (CNFs) were successfully synthesised on a treated commercial steel substrate by catalytic chemical vapour deposition (CCVD) utilising ethanol at 700 °C. The formation of the nanofibers with average diameter of 200–400 nm was confirmed via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. The BET surface area, pore volume and pore size of the obtained CNFs were sequentially: 182 m2/g, 10.5 cm3/g and 103.3 Å as determined by nitrogen adsorption analysis. The influence of the surface treatment on the size and shape of CNFs was investigated and the results indicated a positive correlation that can be employed to tailor CNFs of desired morphology. Accordingly, a growth mechanism due to the deposition of carbonaceous materials on large size nanoparticles was proposed. As the CCVD is a facile and economical route for CNFs synthesis, thus, it can be efficiently adopted for the growth of CNFs on pretreated steel substrates as proved by this study.