We calculate the potential energy surface, the low-frequency vibrational modes, and the electronic structure of a ~5,5!@~10,10! double-wall carbon nanotube. We find that the weak interwall interaction and changing symmetry cause four pseudogaps to open and close periodically near the Fermi level during the soft librational motion at n&30 cm. This electron-libration coupling, absent in solids co...

A network of entangled multiwall carbon nanotubes is an assembly of non-bonded and randomly oriented units whose mechanical behavior is affected by their buckling, compression and slippage at contact points. Slippage and irreversible nanotube rearrangements are evidenced by the hysteresis in the stress-strain curves during loading and unloading cycles. To model the mechanical behavior, a nonlin...

The acid oxidation of carbon nanotube generally results in opening the close ends of the nanotube and to make surface modifications. Herewith, Multiwall carbon nanotubes (MWCNTs) were oxidized in acids at high temperature experimental conditions which led to the formation of graphene quantum dots (GQDs).   High resolution transmission electron microscope (HRTEM), energy dispersive X-ray spectro...

The growth of single wall carbon nanotubes (SWNTs) mediated by metal nanoparticles is considered within (i) the surface diffusion growth kinetics model coupled with (ii) a thermal model taking into account heat release of carbon adsorption-desorption on nanotube surface and carbon incorporation into the nanotube wall and (iii) carbon nanotube-inert gas collisional heat exchange. Numerical simul...

High-resolution CKa spectra have been obtained for samples containing carbon cage particles, synthesized using the arc-discharge graphite evaporation technique. The X-ray fluorescence spectrum of particles from the inner part of the cathode deposit was found to differ from that of the soot collected on the chamber walls. The dependence of the spectral profile on the geometry was investigated us...

Reviewing experimental results and based on the physical reasoning, we present a basic circuit model for Multiwall carbon nanotubes (MWCNTs), which can simulate different experimental results. Investigation of different results confirms the severe effects of fabrication process (nanotube and contacts) on electronic properties of the MWCNTs. The circuit model has been developed to show the perfo...

The acid oxidation of carbon nanotube generally results in opening the close ends of the nanotube and to make surface modifications. Herewith, Multiwall carbon nanotubes (MWCNTs) were oxidized in acids at high temperature experimental conditions which led to the formation of graphene quantum dots (GQDs).   High resolution transmission electron microscope (HRTEM), energy dispersive X-ray spectro...

A novel strategy for the fabrication of multiwall carbon nanotube-nanocrystal heterostructures is shown. Different quantum dots (QDs) with narrow size distributions were covalently coupled to carbon nanotubes (CNTs) and silica-coated CNTs in a simple, uniform, and controllable manner. The structural and optical properties of CNT/QD heterostructures are characterized by electron microscopy and p...

Parallel alignment of nanotubes can be obtained by dispersion in a self-organizing anisotropic fluid such as a nematic liquid crystal. Exploiting the cooperative reorientation of liquid crystals, the overall direction of the nanotube alignment can be controlled both statically and dynamically by the application of external fields. These can be electric, magnetic, mechanic, or even optic in natu...

Enzymatic biofuel cells have many great usages as a small power source for medical and environmental applications. In this paper, we employed carboxylated multiwall carbon nanotube- (1-ethyl-3-methylimidazolium bis (trifluoromethyl sulfonyl) imide) ionic liquid nanocomposite on two different electrodes (glassy carbon and carbon felt) for immobilizing alcohol dehydrogenase. The properties of the...