Carbon nanotube synthesis: from large-scale production to atom-by-atom growth

Abstract

The extraordinary electronic, thermal and mechanical properties of carbon nanotubes (CNTs) closely relate to their structure. They can be seen as rolled-up graphene sheets with their electronic properties depending on how this rolling up is achieved. However, this is not the way they actually grow. Various methods are used to produce carbon nanotubes. They all have in common three ingredients: (i) a carbon source, (ii) catalyst nanoparticles and (iii) an energy input. In the case where the carbon source is provided in solid form, one speaks about 'high temperature methods' because they involve the sublimation of graphite which does not occur below 3200 °C. The first CNTs were synthesized by these techniques. For liquid or gaseous phases, the generic term of 'medium or low temperature methods' is used. CNTs are now commonly produced by these latter techniques at temperatures ranging between 350 and 1000 °C, using metal nanoparticles that catalyze the decomposition of the gaseous carbon precursor and make the growth of nanotubes possible. The aim of this review article is to give a general overview of all these methods and an understanding of the CNT growth process.

Effect of Co and Ni nanoparticles formation on carbon nanotubes growth via PECVD

“…Based on the results, the slower growth rate in thinner catalyst is possibly due to greater supersaturation rate of carbon feedstock, resulting in formation of a carbon shell around the catalyst instead of the nanotube structure which stops the nanotube formation at earlier stage. [9] This indicates that a lower supply of carbon feedstock is required when utilising a thinner catalyst film for CNTs growth. However, the average growth rate of Co catalyst is about 1.5 times higher than Ni catalyst which significantly shows that Co catalyst has better role in improving the growth rate.…”

“…SWCNTs are of tubular structure formed by wrapping a single-layer graphene sheet, whereas MWCNTs consist of multiple graphitic layers where the interlayer distance is approximately 0.34 nm. [8,9] In the past two decades, arc discharge, [10] laser ablation, [11] and chemical vapour deposition (CVD) [12] methods have been developed for CNTs production in large quantities as massive production of CNTs is required for most applications. Various methods existed to produce CNTs but they all have three ingredients in common which consist of carbon source, catalyst nanoparticles and input energy.…”

One-Dimensional Carbon Nanostructures—From Synthesis to Nano-electromechanical Systems Sensing Applications—

“…Mechanically speaking, CNTs have a high Young's modulus (around 1 TPa) and are potentially 30 to 100 times stronger than steel. (12)(13)(14)(15)(16)(17) Besides, they are the best in conducting both heat and electricity. (12)(13)(14)(15)(16)(17) Table 3 summarizes some of these properties.…”

Effects of Magnetic Field and Gravity on Single-Walled Carbon Nanotube Production in Three Directions of Arc Discharge Current

“…Among the available production techniques, arc discharge is one of the most efficient techniques for producing SWNTs [2,3]. In this method, a carbon rod is sublimated in He gas at a temperature of ~5000 , and carbon atoms are reacted in the gas phase where there is a strong temperature gradient [3,4,5].…”