Catalysis and Chemical Engineering Global Conference

Catalysis plays a very important role in the synthesis of carbon nanotubes, which are highly valued for their exceptional strength and conductivity both electrically and thermally. These spectacular properties make CNTs dramatically useful in fields as diversified as electronics and materials science to biomedical engineering. Catalytic processes broadly contribute to producing copious high-quality carbon nanotubes with considerable efficiency.

In the catalytic synthesis of CNTs, catalysts tend to appear as metal nanoparticles, such as iron, cobalt, or nickel, that assist in the induction of growth from carbon-containing gases, such as methane or acetylene. Decomposition of the gas at very high temperatures would likely release carbon atoms, which could then start to assemble on the surfaces of the catalyst particles, forming cylindrical structures that grow to form nanotubes. Such a technique, commonly referred to as chemical vapor deposition (CVD), has gained popularity because of the excellent control over the diameter, length, and other details of the nanotube structure that can be designed for specific applications.

PECVD (Plasma-enhanced chemical vapor deposition) is another route in the synthesis of CNTs. It includes plasma-generated energy during synthesis to allow the formation of CNTs at a relatively low temperature. Of all these routes, electronics is most useful, where devices are grown directly on substrates such as field-effect transistors and sensors, among others. Good control over the catalyst material and synthesis conditions allows highly aligned and vertically oriented carbon nanotubes to be produced, suited well to electronic and optical applications.

Catalysis is not only improving the efficiency of the synthesis of CNTs but also providing varied types of nanotubes, namely, single-walled and multiwalled carbon nanotubes. Single-walled CNTs possess outstanding electrical properties and have potential in nanoelectronics applications. Multiwalled CNTs are advantageous because of their good mechanical strength, allowing them applications in composite materials for aerospace and automotive industries.