The influence of preparation parameters on the mass production of vapor-grown carbon nanofibers

An effective production of pure vapor-grown carbon nanofibers (VGCNFs) was obtained at the temperature of 1373-1473 K in the presence of sulfur by an improved floating catalyst method in a horizontal reactor using benzene as carbon source, ferrocene as catalyst precursor and hydrogen as carrier gas. It was Found that higher than 30 wt.% of the carbon source from benzene can be transformed to VGCNFs which are very pure and straight, and have uniform diameters. The experimental results demonstrated that the concentration of the sulfur-containing compound (thiophene) together with the molar ratio of C6H6/H-2, the gas residence time and the reaction time strongly influenced the yield of VGCNFs. (C) 2000 Elsevier Science Ltd. All rights reserved.