Tailoring the diameters of vapor-grown carbon nanofibers

Abstract

Diameters in the range 40–300 nm for vapor-grown carbon nanofibers (VGCNFs) can be tailored using synthesis parameters with a floating catalyst method at temperatures of 1373–1473 K in the presence of sulfur. The VGCNFs obtained are found to be very pure and straight, and have uniform diameter within each batch for certain parameters. A lower molar ratio of C/H, appropriate molar ratio of S/C, and suitably higher flow-rate of the mixture of hydrogen and benzene help the growth of carbon nanofibers with smaller diameters. If the synthesis parameters are carefully controlled, our results show that VGCNFs with diameters of 5–40 nm can also be obtained.