Aligned Nanotubes

Abstract

Since the discovery of carbon nanotubes by lijima in 1991, various carbon nanotubes with either a single- or multilayered graphene cylinder(s) have been produced, along with their noncarbon counterparts (for example, inorganic and polymer nanotubes). These nanostructured materials often possess size-dependent properties and show new phenomena related to the nanosize confinement of the charge carriers inside, which leads to the possibility of developing new materials with useful properties and advanced devices with desirable features for a wide range of applications. In particular, carbon nanotubes have been shown to exhibit superior properties attractive for various potential applications, ranging from their use as novel electron emitters in flat-panel displays to electrodes in electrochemical sensors. For many of the applications, it is highly desirable to have aligned/patterned forms of carbon nanotubes so that their structure/property can be easily assessed and so that they can be effectively incorporated into devices. In this Review, we present an overview on the development of aligned and micropatterned nanotubes, with an emphasis on carbon nanotubes.

Carbon Nanotube Supercapacitors

“…A wide range of approaches have been developed to synthesize CNTs including, for example, carbon arc-discharge (Ebbesen & Ajayan, 1992) and pyrolysis of hydrocarbons (Harris, 1999) for MWNTs, carbon arc-discharge (Harris, 1999), pulsed laser vaporization (Journet et al, 1997;Thess et al, 1996) and pyrolysis of hydrocarbons or carbon monoxide (Zheng et al, 2002) for SWNTs, chemical vapor deposition for aligned MWNTs (Dai, 2006;Dai et al, 2003;Harris, 1999), and plasma-enhanced chemical vapor deposition for aligned SWNTs. Depending on their diameter and helicity of the arrangement of carbon atoms in the walls, CNTs can exhibit semiconducting or metallic behavior (Dai, 2006;Harris, 1999), with an electrical conductivity as high as 5000 S/cm (Dresselhaus, 1996).…”

Controlled Growth-Reversal of Catalytic Carbon Nanotubes under Electron-Beam Irradiation

“…The catalytic growth of carbon nanotubes is currently the method of choice for growing vertically-aligned patterned arrays for a wide range of electronic, gas sensing and biological applications [1][2][3] . Significant advances in the understanding of the growth processes have generally been linked to their in-situ observation [4][5][6][7][8] , usually in specially-modified electron microscopes.…”

Synthesize multi-walled carbon nanotubes via catalytic chemical vapour deposition method on Fe-Ni bimetallic catalyst supported on kaolin

“…Furthermore, the production of CNTs using the CCVD technique has been found to depend on the type of carbon source, catalyst, growth time, and growth temperature [6][7][8]. Previously, Shah and Tali [8] found that inert methane and carbon monoxide produced single-wall CNTs (SWCNTs), while Dia et al [11] and Yardimci et al [12] independently demonstrated that unsaturated hydrocarbons such as acetylene can be used for multi-walled CNT (MWCNT) growth. Similarly, Chiwaye et al [13] and Liu et al [14] concluded that acetylene gas remained the most reactive unsaturated hydrocarbon and was most frequently employed for the growth of MWCNTs.…”