The electrical resistance of mats of single-wall carbon nanotubes (SWNTs) is measured as a function of mat temperature under various helium pressures, in vacuum and in atmospheric air. The objective of this paper is to study the thermal stability of SWNTs produced in a helium arc discharge in the experimental conditions close to natural conditions of SWNT growth in an arc, using a furnace inste...

Photoluminescence (PL) dynamics in single-walled carbon nanotubes (SWNTs) has been studied by the femtosecond excitation correlation method with a 150 fs time resolution. The SWNT samples were synthesized by different methods and suspended in gelatin films or D2O solutions. The PL dynamics of SWNTs depends on the local environment surrounding the SWNTs rather than the synthesis methods. The ver...

A new poly(N-vinylcarbazole)-covalently grafted single-wall carbon nanotube (SWNT-PVK) hybrid material was synthesized by an in situ anionic polymerization reaction of N-vinylcarbazole and the negatively charged SWNTs. Incorporation of the PVK moieties onto the SWNTs' surface considerably improves the solubility and processability of SWNTs. At the same level of linear transmission, the SWNT-PVK...

Different catalyst formulations and reaction conditions have been used to test the validity of a hypothesis that tries to elucidate the mechanism of single-walled nanotube (SWNT) formation by CO disproportionation over a highly selective cobalt-molybdenum catalyst. This model proposed an intrinsic dependence between the selectivity of the catalysts toward SWNT and the stabilization of Co specie...

Single-walled carbon nanotubes (SWNTs) are dispersed in water via wrapping with short segments of single-stranded DNA (ssDNA). Small angle neutron scattering suggests a power-law exponent that is consistent with clustered nanotubes and hence marginal stability. The SWNT-ssDNA complex is used to stabilize dispersions of hydrophilic colloidal particles with the nanotubes adhered to the surface of...

Peapods present a model system for studying the properties of dimensionally constrained crystal structures, whose dynamical properties are very important. We have recently studied the rotational dynamics of C(60) molecules confined inside single walled carbon nanotube (SWNT) by analyzing the intermediate frequency mode lattice vibrations using near-infrared Raman spectroscopy. The rotation of C...

Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. Nanotubes have been synthesized with length-to-diameter ratio of up to 132,000,000 : 1, which is significantly greater than any other material. These cylindrical carbon molecules have novel properties which make them potentially useful in many applications in nanotechnology, electronics, optics, and other fields ...

Luttinger liquid theory predicts that collective electron excitations due to strong electron-electron interactions in a one-dimensional (1D) system will result in a modification of the collective charge-propagation velocity. By utilizing a circuit model for an individual metallic single-walled carbon nanotube as a nanotransmission line, it has been shown that the frequency-dependent terahertz i...

We report the synthesis, characterization and photophysical features of a new nanometer scale carbon nanostructure, that is, a single-wall carbon nanotube bearing phthalocyanine chromophores.

We present a measurement protocol that effectively eliminates both the hysteresis and the temporal drift typically observed in the channel conductance of single-walled carbon nanotube field-effect transistors (SWNT FETs) during the application of gate voltages. Before each resistance measurement, the gate is first stepped through a series of alternating positive and negative voltages to produce...