Carbon Nanotubes: Their Role in Engineering Applications

Carbon Nanotubes: Their Role in Engineering Applications

Since the discovery of carbon nanotubes by Iijima in 1991, they have been of great interest because of their simplicity and ease of synthesis. The novel properties of nanostructure carbon nanotubes such as high surface area, good stiffness, and resilience have been explored in many engineering applications. Research on Carbon nano tubes have shown the application in the field of energy storage, hydrogen storage, electro-chemical super capacitor, field emitting devices, transistors, nano probes and sensors, composite material, templates, etc. For commercial applications large quantities and high purity of carbon nanotubes are needed. Different types of carbon nanotubes can be synthesized in various ways. The most common techniques currently practised are, arc discharge, laser ablation, and chemical vapor deposition and flame synthesis. The purification of CNTs are carried outusing various techniques mainly oxidation, acid treatment, annealing, sonication, filtering, chemical functionalization etc. However, high purity purification techniques still have to be developed. Real applications are still under development. This paper addresses the current research on the challenges that are associated with synthesis methods, purification methods, dispersion and toxicity of CNTs within the scope of different engineering applications, energy and environmental impact.