Low-temperature growth of carbon nanofiber by thermal chemical vapor deposition using CuNi catalyst

Thermal-CVD was carried out for the low-temperature growth of carbon nanofibers (CNFs) using a CuNi alloy catalyst film with a thickness of 5 nm on Si in a gas mixture of C2H2 and He (C2H2/He = 3/12 sccm). The experimental results obtained using the CuNi alloy catalyst film were compared with those obtained using the Fe, Ni, and FeNi catalyst films with the same thickness of 5 nm. It was shown that an amorphous CNF with a diameter of 20 urn can be grown even at 400 degrees C using the CuNi catalyst film. but not using the Fe, Ni and FeNi catalysts. A reduction in the growth temperature of CNFs was considered to be achieved using small CuNi catalyst particles with a comparatively smaller surface energy than FeNi catalyst particles.