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The article discusses the application of the microwave plasma chemical vapor deposition method for the growth of 0.5 cm vertically aligned single-walled carbon nanotubes. The growth rate of the nanotubes is shown to be limited by the gas phase diffusion of the hydrocarbon radicals.

Large mats of dense, well-aligned, multiwalled carbon nanotubes (CNTs) are grown with a vapor-phase chemical vapor deposition (CVD) method by using ferrocene and benzene as reactants and are then tested by using a thermomechanical analyzer and a scanning electron microscope. The analysis of both the growth method used and the nanotube mat fracture surface has indicated that the mats grown in this method are not made of continuous nanotubes and their strengths are actually closer to those of woven nanotube yarns and ropes.

The structural properties of water molecules confined in functionalized carbon nanotubes (CNTs) are studied using molecular dynamics (MD) simulations. The incurvature or extracurvature configurations of --COOH groups are found to be the result of synergy effects of the CNTs helicity and diameter and control of the flow direction of water molecules in CNTs.

Single-walled carbon nanotubes (SWNTs) were found to have significant interaction with poly(2-hexylthiophene) (P3HT), which helps in forming continuous active film with interpenetrating structure and improving the crystallinity of the resultant film for SWNTs/P3HT composite. Photovoltaic devices based on an active film with relatively higher crystallinity exhibit much enhanced performance.

The structures of small silicon (Si) clusters that are formed on the surfaces of the carbon nanotubes, which exist as three-dimensional figures instead of the usually found sheets, are studied. The results show that the lowest-energy clusters have very different structures, as compared to the prolate structures and finally result in the formation of a compact spherical structure with the interior atoms.

Chemical vapor deposition (CVD) synthesizes highly aligned arrays of multiwalled carbon nanotube (MWCNT) on layered Si substrates and the effect of substrate design and the process parameters on the growth mechanism are studied. The characterization study has displayed catalyst island formation before nanotube array growth and nanotube growth on the top of the array.

A method to prepare multi-walled carbon nanotube (MWCNT) films, cross-linked though ester bonds, by a condensation reaction in the presence of 1, 3-dicyclohexylcarbodiimide (DCC) is presented. The structure is verified by Fourier transform-infrared spectroscopy and the tensile strength and Vickers hardness of condensed-MWCNT films were found to be more than those with free-standing MWCNT films without ester bonds.

The performance of the aqueous solution of nanotubes that fills the two-phase closed thermosyphon or a gravity-assisted heat pipe is examined. The results have shown that alterations of solid-liquid-vapor interfacial properties, arising from the addition of carbon nanotubes, have changed the boiling mechanism, thus deteriorating the boiling heat transfer.

The process of rare-gas atoms (He, Ne, Ar, Kr, Xe) injected into single-walled carbon nanotube (SWNT) and the mechanical oscillatory behavior of rare-gas atoms sliding in a SWCNT by using molecular dynamics simulations is investigated. It is found that the oscillatory frequencies are insensitive to the initial kinetic energy but they are sensitive to the lengths and the radius of the tube and they decrease as the length and the radius of the tube increases.

The deposition of multiwalled carbon nanotubes modified by poly(2-vinylpyridine) (CNT-g-P2VP) from aqueous dispersions at low pH is found to be an effective method to prepare homogeneous ultrathin films with a tunable CNTs density. Although the multiwalled CNT films are less conductive and less transparent than the SWNT films, they might be used in touch screens, reflective displays, EMI shielding and static charge dissipation.

The advance in the bulk purification of nitric acid-treated single-walled carbon nanotubes (SWNTs) is described by using high-speed centrifugation. The efficiency of the process is confirmed by the high purification recovery factor and it is shown that the purity of SWNTs affects their mechanical and electrical properties.

A simple and direct synthetic method is described for the preparation of nanoporous carbon nanotubes with larger pores (>10 nm) on the tube walls. The method combines the use of anodic aluminum oxide (AAO) as a template for the tube diameter and block copolymer/carbohydrates self-assembly within thin films confined inside AAO pore channels to form nanopores.

Intense research efforts are made to synthesize aligned long carbon nanotube (CNTs), owing to outstanding mechanical and electrical properties of CNTs. In result, the method of growing ultralong multi-walled nanotubes, including single-walled nanotubes by adjusting the diameter dependent Reynold number and the concentration of catalytic precursor, is developed.

The advances in the design, synthesis, characterization, and potential applications of new hybrid materials are studied based on carbon nanotube and electron donors to prepare practical photoelectrochemical devices. The ultimate goal of using these systems to prepare practical photoelectrochemical devices is discussed and a cell with a monochromatic efficiency of 8.5% conversion of light into current is illustrated.

The ensemble Monte Carlo transport simulations for semiconducting, single-wall, zigzag carbon nanotubes is reported. The results show interesting transient phenomena that are caused by the limited phase space of these dynamically one-dimensional structures.

Byline: C. Gomez-Navarro, P.J. De Pablo, J. Gomez-Herrero A fundamental requirement for a molecule to be considered a molecular wire (MW) is the ability to transport electrical charge with a reasonably low resistance. From this point of view, we performed experiments of electrical transport on carbon nanotubes and individual DNA molecules. By using a conductive atomic force microscopy (AFM) tip as a mobile electrode, we can experimentally determine the electron mean free path of carbon nanotubes with one end connected to a macroscopic gold electrode. We also investigated the radial electromechanical properties of carbon nanotubes by using AFM, showing that when a high strain is applied to the nanotube a gap in the electronic band structure of the tube is opened. Finally we show how the electrostatic force between the carbon nanotubes and the AFM tip can be used to investigate the conductance properties of carbon nanotubes. When similar experiments are performed on single DNA molecules, we do not find any traces of conductance.

The preferential growth of single-walled carbon nanotubes (SWNTs) on silica spheres with various diameters was realized for the first time by chemical vapor deposition (CVD) of methane. The study shows that the combination of SWNTs with monodispersed silica spheres could conveniently integrate SWNTs into photonic crystals.

A hierarchical multiscale methodology linking molecular dynamics and the finite element method through atomically informed cohesive zone model parameters to represent interfaces is developed to study the atomic scale interface effects on composite behavior. The developed methodology is used to study the effect of interface strength on stiffness of the carbon nanotubes (CNT)-based composite.

The electrical properties of mechanically deformed single-walled carbon nanotubes (SWNTs) are examined. The effect of mechanical deformation on the electrical transport properties of nanotubes is studied using a tight-binding method.

A newly developed method for modeling the deformation of single and multi-wall carbon nanotubes is applied to nanotube buckling under axial compression. The insufficiency of assigning the shell density as the balance spacing of graphite planes is clearly indicated.

Carbon nanotubes have many exceptional mechanical and electronic characteristics originating from their unique geometric and chemical structures. The current status of the various experimental studies of their basic mechanical properties is reviewed.

A combination of various modeling methods is used to show the impact of uniform deformation on the characteristics of a variety of single wall carbon nanotubes. Significant observations related to the link between mechanical and electrical behavior are presented.

A detailed study on the coefficient of thermal expansion (CTE) of carbon nanotubes (CNT) including their temperature dependence is presented. An analytical process to ascertain the CTE for single wall CNT has been designed.

An extensive investigation of the hardening effect of carbon nanotubes by micromechanics methods is presented. The impacts of the noted waviness and agglomeration of the carbon nanotubes are hypothetically examined.

Tribology is related to the adhesion and friction between two material surfaces brought into contact. The possibility of unusual tribological actions for two surfaces covered with aligned single-walled carbon nanotubes is studied.

The atomistic observations of single-wall carbon nanotubes with significantly big ratios subject to compressive loading are presented. Three distinct categories of mechanical reactions to the compressive loading are identified.

The fracture strength of highly ordered carbon-nanotube-reinforced alumina composites is computed using experimental data on nanoindentation cracking. The results indicate that the residual pressure and nanotube connection play crucial roles in the nanocomposite fracture.

The molecular dynamics, continuum and combined simulation of carbon nanotube based nanoelectromechanical switches are reported. The pull-in voltage features of a nanoelectromechanical switch are studied.

The role of the metal particle in the formation of nanotubes synthesized by plasma enhanced chemical vapor deposition (PECVD) is discussed. It is found that varying growth temperature catalytic particles of different shape and size can be formed.

A new chromatographic purification of soluble single-walled carbon nanotubes is presented using the gel permeation chromatography technique. These purified nanotubes possess very important mechanical, thermal and electronic properties.

A micromechanics approach for assessing the impact of an interfacial thermal resistance, also known as the Kapitza resistance, on the effective thermal conductivity of carbon nanotube-polymer nanocomposites is applied, which includes both the effects of the presence of the hollow region of the carbon nanotube (CNT) and the effects of the interactions amongst the various orientations of CNTs in a random distribution. The interfacial thermal resistance is a nanoscale effect introduced in the form of an interphase layer between the CNT and the polymer matrix in a nanoscale composite cylinder representative volume element to account for the thermal resistance in the radial direction along the length of the nanotube. The end effects of the interfacial thermal resistance are accounted for in a similar manner through the use of an interphase layer between the polymer and the CNT ends. Resulting micromechanics predictions for the effective thermal conductivity of polymer nanocomposites with randomly oriented CNTs, which incorporate input from molecular dynamics for the interfacial thermal resistance, demonstrate the importance of including the hollow region in addition to the interfacial thermal resistance, and compare well with experimental data. Keywords: carbon nanotube, nanocomposite, thermal conductivity, micromechanics, composite cylinders