Abstract

An optimum route to synthesize Al_2O_3-based composite powders with homogeneous dispersion of carbon nanotubes (CNTs) was investigated. CNTs/Metal/Al_2O_3 nanocomposite powders were fabricated by thermal chemical vapor deposition of C_2H_2 gas over metal/Al_2O_3 nanocomposite catalyst prepared by selective reduction of metal oxide/Al_2O_3 powders. The FT-Raman spectroscopy analysis revealed that the CNTs have single- and multi-walled structure. The CNTs with the diameter of 25-43 nm were homogeneously distributed in the metal/Al_2O_3 powders, and their characteristics were strongly affected by a kind of metal catalyst and catalyst size. The experimental results show that the composite powder with required size and dispersion of CNTs can be realized by control of synthesis condition.

• Keywords: Carbon nanotubes;Thermal CVD;Nanocomposite powders;Microstructure;