For the purpose of low cost and sensitive electrochemical detection of 17 beta-estradiol (E2), a multi-wall carbon nanotube (MWNT)-Nafion modified electrode was fabricated. The MWNT modified electrode shows enhancement for the anodic peak current of E2 compared with the value obtained using a bare electrode. The anodic peak current measured by square wave voltammetry after 5 min open-circuit ac...

A facile, two-step method for chemically attaching single-stranded DNA to graphitic surfaces, represented here by carbon nanotubes, is reported. In the first step, an azide-containing compound, N-5-azido-nitrobenzoyloxy succinimide (ANB-NOS), is used to form photo-adducts on the graphitic surfaces in a solid-state photochemical reaction, resulting in active ester groups being oriented for the s...

Field emission studies were conducted on as-produced CoMoCAT single-walled carbon nanotube/silica composites with controlled nanotube diameter and bundle size. It has been observed that the as-produced nanotube material does not need to be separated from the high-surface area catalyst to be an effective electron emitter. By adjusting the catalytic synthesis conditions, single-walled carbon nano...

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...

Three different carbon-based counter electrodes are investigated in light of catalytic activities such as electrochemical frequencies and interface impedances. We fabricated carbon-based counter electrodes of dye-sensitized solar cells [DSSCs] using graphene, single-walled carbon nanotubes [SWNTs], and graphene-SWNT composites by electrophoretic deposition method. We observed the optical and el...

In this paper, (10, 0) zigzag nanotubes and (6, 6) armchair nanotubes are considered to investigate the effects of randomly distributed vacancy defects on mechanical behaviors of single-walled carbon nanotubes. A spatial Poisson point process is employed to randomly locate vacancy defects on nanotubes. Atomistic simulations indicate that the presence of vacancy defects result in reducing nanotu...