The chemical reactivity of carbon nanotubes in H2SO4 is investigated using individual, single-walled carbon nanotubes (SWNTs) incorporated into electronic devices. Exploiting the device conductance as a sensitive indicator of chemical reactions, discrete oxidation and reduction events can be clearly observed. During oxidation, a SWNT opens circuits to a nanometer-scale tunnel junction with resi...

We have found that racemic mixtures of chiral single-walled nanotubes (SWNTs) wrapped with d(GT)20 DNA oligomer exhibit circular dichroism (CD). We attribute the CD signal to induced CD arising from the coupling of transition moments of the SWNTs and the DNA. Although the nanotube mixture appears to contain both enantiomers in equal amounts, DNA-SWNT transition moment interaction is more constr...

Infrared reflection-absorption spectroscopic measurements have been performed on single-wall carbon nanotubes (SWNTs), cleaned by heating to approximately 500 degrees C in vacuo, during exposure to pure 16O2 or 18O2 at room temperature and at pressures of up to approximately 630 Torr. No vibrational signature of any form of adsorbed O is detected. However, structure is seen which is very simila...

The polymer possessing with planar structure can be activated and guided to encapsulate the inner space of SWNT and form a helix through van der Waals interaction and the π-π stacking effect between the polymer and the inner surface of SWNT. The SWNT size, the nanostructure and flexibility of polymer chain are all determine the final structures. The basic interaction between the polymer and the...

The interaction force between functionalized single-walled carbon nanotubes (SWNTs) plays an important role in the fabrication of self-assembled and highly ordered SWNT arrays for a wide range of potential applications. Here, we measured interaction force between SWNTs encapsulated with polymerized surfactant monolayer (p-SWNTs). The balance between the repulsion between p-SWNTs and the osmotic...

Carrier transport characteristics in high-efficiency single-walled carbon nanotubes (SWNTs)/silicon (Si) hybrid solar cells are presented. The solar cells were fabricated by depositing intrinsic p-type SWNT thin-films on n-type Si wafers without involving any high-temperature process for p-n junction formation. The optimized cells showed a device ideality factor close to unity and a record-high...

Results are presented of in situ studies of the thermoelectric power and four-probe resistance of single-walled carbon nanotube films during the adsorption of cyclic hydrocarbons C(6)H(2n) (n=3-6). The size of the change in these transport parameters is found to be related to the pi electron population of the molecule, suggesting the coupling between these pi electrons and those in the nanotube...

In the liquid-based dip-coating, the hydrophilicity of a Si/SiO(2) substrate is found to be critical for the successful deposition of catalyst and hence the growth of single-walled carbon nanotubes (SWNTs). When the surface is functionalized by a self-assembled monolayer (SAM) and becomes hydrophobic, no catalyst remains and no SWNT grows. This concept can be utilized to localize the growth of ...

We have investigated the photoluminescence (PL) of in individual single-walled carbon nanotubes (SWNTs) placed in field-effect transistor structures to study carrier transport in the SWNT. The relation between the recombination lifetime and carrier transit time has been evaluated from the drain-field dependence of PL intensity. Time-resolved photoluminescence of SWNTs dispersed in surfactant so...

In spite of the outstanding properties of single-walled carbon nanotubes (SWNTs), the coexistence of metallic and semiconducting SWNTs as a result of synthesis has hindered their electronic and photonic applications. We demonstrate a pump-probe microscopy method for fast, contact-free mapping of metallicity in individual SWNTs. We employ the phase of transient absorption as a contrast to discri...