6. Characteristics of Carbon Nanotubes

Carbon nanotubes (CNTs) are the materials of modern age having diverse applications in every sector. This article discusses the structure, synthesis, properties, purification, and application aspects of CNTs. CNTs can be classified based on tube structure and shapes. This chapter elaborates single-walled nanotubes (SWNTs), multi-walled nanotubes (MWNTs), and double-walled nanotubes (DWNTs) in brief. In addition, researches are going on worldwide to generate CNTs of variable shapes such as coiled, waved, bent, beaded, junction CNTs. CNTs can be synthesized by chemical and physical routes. The most common method of CNT production is chemical vapour deposition (CVD) technique that can produce pure CNTs in large quantities. This article also opens up the present aspects of growth mechanism of CNTs. The unique combination of electrical, thermal, and mechanical properties of CNTs makes them a potential performer in the number of fields such as supercapacitors, fuel cells, energy devices, high strength composites, biomedical, chemical. However, the application of CNTs is still somehow limited and yet to reach the desired plateau due to the purification, large-scale production, and toxicity issues.