Acetylene decomposition to helical carbon nanofibers over supported copper catalysts

The helical carbon nanofibers (CNFs), synthesized at relatively low temperatures (lower than 250 deg. C) by using Cu as a catalyst, SiO{sub 2}, TiO{sub 2}, Al{sub 2}O{sub 3}, MgO as supports and acetylene as gas source, has been investigated. The products were characterized by field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD). The morphologies of obtained products influenced by the types of supports and weight ratios (Cu/support = 1:1, 1:5, and 1:10) were discussed. The average diameter of the helical CNFs was about 80 nm, and these CNFs had the same coil pitch, and coil diameter.