How Catalysts Affect the Growth of Single‐Walled Carbon Nanotubes on Substrates

Abstract

Direct growth of single-walled carbon nanotubes (SWNTs) on flat substrates by chemical vapor deposition (CVD) is very important for the application of SWNTs in nanodevices. In the growth process, catalysts play an important role in controlling the structure of SWNTs. Over the years, we have systematically studied the size-controlled synthesis of Fe-based nanoparticles and the CVD growth of SWNTs, especially the horizontally aligned SWNTs, catalyzed by these produced nanoparticles. Some new catalysts were also developed. Among them, Cu is shown to be a superior catalyst for growing SWNT arrays on both silicon and quartz substrates and Pb is a unique catalyst from which one can obtain SWNTs without any metallic contaminant. SWNTs prepared with both Cu and Pb are very suitable for building high-performance nanodevices. These studies are also very helpful for further understanding the growth mechanism of SWNTs.

A review of the large-scale production of carbon nanotubes: The practice of nanoscale process engineering

“…To date, the only effective method to prepare these materials is with gas-flow-directed CVD on a Si substrate [9,10,24,25]. In this method, catalyst particles catalyze the decomposition of the carbon source to provide carbon atoms and the gas flow provides the buoyancy for suspended tubes to grow without resistance.…”

“…Many other articles have reviewed the growth of singleand multi-walled carbon nanotubes, using either arc discharge, laser ablation, or catalytic CVD techniques [4][5][6][7][8][9][10][11][12][13][14][15][16].…”

Direct growth of single-walled carbon nanotubes on substrates

“…(c) Scheme of a serpentine SWNT on quartz [13]. (d) SEM image of SWNT arrays grown on quartz using ethanol as carbon source [14]. nanotubes (MWNTs) and SWNT bundles are almost avoided with the substrate oriented growth.…”

“…Therefore, the type, morphology and properties of the catalyst particles play important roles in determining the structure and quality of the SWNTs. Catalyst is an essential factor in the controlled growth of SWNTs [14].…”

“…Recently, many reports have shown that the composition, size, and structure of the catalyst particles may affect the structure of SWNTs [14][15][16][17][18][19][20][21][22]. We should put more efforts on understanding the growth mechanism of SWNTs and the design of catalysts.…”