Current Synthetic Methodologies of Carbon Nanotubes: A Review

Carbon Nanotubes (CNTs) possess a unique one-dimensional molecular geometry with a large surface area. Recently, CNTs have become a thrust area of research as they play a crucial role in molecular engineering due to their excellent mechanical, electrical, and thermal properties. CNTs have a wide range of applications in various fields due to their unique properties. The Multiple Walled Carbon Nanotubes (MWCNTs) are thermally, mechanically, and structurally stronger than single-walled carbon nanotubes (SWCNTs). The sublimation of carbon in an inert atmosphere is the basis of synthetic methods of CNTs like the solar method, laser ablation, and electric arc discharge. Specific chemical methods like CVD, electrolysis, catalytic decomposition of hydrocarbons, heat treatment of a polymer, ball milling, etc., can also be used to prepare CNTs. Attempts have been made in the present review to discuss all synthetic methods of CNTs, their discoverers, the importance of techniques, various parameters that affect the process in detail, and the mechanism for the growth of CNTs. This article aims to provide a comprehensive pathway for researchers who deal with the synthetic methodology of carbon nanotubes. This review is also interesting for readers of material science and nanochemistry.