Growth and characterization of bamboo-shaped carbon nanotubes using nanocluster-assembled ZnO:Co thin films as catalyst

In this work, bamboo-shaped CNTs were successfully fabricated by PECVD using ZnO:Co thin film as catalyst. ZnO:Co nanoclusters were produced by a nanocluster-beam deposition system. Briefly, a metal target consisting of 98% Zn and 2% Co was used with a sputtering power of 130 W. Ar, He and Oxygen gases were injected into the system with the corresponding total pressure of 0.75 Torr. A plasma enhanced chemical vapor deposition (PECVD) system was used to synthesize the CNTs. Before the CNTs growth, the mixture gases of ammonia and acetylene C₂H₂ were introduced into the system. The pressure inside the plasma chamber was maintained at 13 mbar. During the growth of CNTs, a 500 V of biased voltage was applied throughout the 15 min CNT growth process.