Low-temperature synthesis of multi-walled carbon nanotubes over Cu catalyst

It is well known that Fe, Co, Ni, and their alloy are the effective catalyst components in chemical vapor deposition growth of carbon nanotubes (CNTs), while Cu has low catalytic activity owing to its nearly zero carbon solubility. In this paper, a simple and effective approach was developed to synthesize multi-walled CNTs using unmodified Cu catalyst supported on Al matrix under a low temperature (600 °C). The obtained CNTs with bamboo-like structure are mainly composed of well-crystallized graphite. It is found that the Al carrier plays a key role in the catalytic growth of CNTs, signifying a new way for low-temperature synthesis of multi-walled CNTs.

► MWCNTs were synthesized by using Cu catalyst at a low temperature (600 °C).
► The Cu catalyst we used was not modified in acid–base properties.
► Al was first used to support the Cu catalyst in the synthesis of MWCNTs.
► The Al carrier plays a key role in the catalytic growth of MWCNTs.