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Showing 1 to 20 of 154 for “"single-walled carbon nanotubes"”.
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Gas phase production of single-walled carbon nanotubes
Single-walled carbon nanotubes have been produced in a continuous flow gasphase catalytic growth process, in a heated flow of carbon monoxide at pressures of 1--10 atmospheres and temperatures of 800--1200°C. Catalytic cluster nuclei for the nanotubes are generated in situ by thermal …
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Charging and defects in single-walled carbon nanotubes
Single-Walled Carbon Nanotubes (SWCNTs) have been one of the most intensively studied materials. Because of their single-atomic-layer structure, SWCNTs are extremely sensitive to environmental interactions, in which charge transfer and defect formation are the most notable effects. Among a number …
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Resonance Raman spectroscopy of single-walled carbon nanotubes
… properties of phonons in crystalline arrays of carbon nanotubes is presented. The main technique for probing the phonon spectra is Raman spectroscopy and the many unique and unusual features of the Raman spectra of carbon nanotubes are highlighted. Various features of the first-order Raman …
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Controlled multi-step purification of single-walled carbon nanotubes
… to remove iron impurity and non-nanotube carbon materials from raw single-walled carbon nanotubes produced in the HiPco (high pressure CO) process. In this study, iron nanoparticles, coated by carbon, are exposed and oxidized by multiple step oxidation at increasing temperatures. To avoid …
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Applications of Single-Walled Carbon Nanotubes in Organic Electronics
… of materials. In particular, allotropes of carbon interest researchers for their electronic applications. Knowledge of carbon allotropes and their applications has expanded significantly since the discovery of C60 Buckminsterfullerene in 1985, the discovery of multi- and single-walled carbon …
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Gas chromatography on self assembled single walled carbon nanotubes
Carbon nanotubes (CNTs) are nano-sized carbon-based sorbents, which have high surface area, large aspect ratio, can be self-assembled and are known to be stable at high temperatures. It is therefore conceivable that separation techniques, such as, gas chromatography (GC) can benefit from their …
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Single chirality single-walled carbon nanotubes : isolation and application
Single Walled Carbon Nanotubes are of great interest as a semiconducting material with diameters around 1nm and length in the 100s of nm to mm range. The large aspect ratio, near-infrared wavelength bandgap and a high conductivity enable a large number of optical and optoelectronic applications …
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Higher-Order Assemblies of Flavin-Wrapped, Single-Walled Carbon Nanotubes
<p>Individualization of carbon nanotubes is of paramount importance in being able to access their unique physical and optoelectronic properties[<a title="O'Connell, 2002 #10">1</a>]. While stable dispersions of individualized carbon nanotubes can be prepared through a number of different means[<a …
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Advanced purification of aligned arrays of single-walled carbon nanotubes
… the large variety of semiconducting materials, single walled carbon nanotubes (SWNTs) are extremely attractive due to their outstanding charge transport properties and ultrathin bodies. One of the most daunting challenge, however, is in creating large-area, perfectly aligned arrays of purely …
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Evaluations of single walled carbon nanotubes using resonance Raman spectroscopy
… to evaluate the vibrational properties of single walled carbon nanotubes (SWNTs). In the first study, we report an evaluation of second-order combination and over-tone modes in highly ordered pyrolytic graphite (HOPG), in SWNT bundles, and in isolated SWNTs. We found both dispersive and …
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Biomedical studies of single -walled carbon nanotubes using near-infrared fluorescence
… providing a scientific foundation for the use of single-walled carbon nanotubes (SWNTs) in biomedical applications. SWNTs have been found to be a unique class of nanoscale near-infrared (NIR) fluorescence contrast agents that also exhibit novel therapeutic capabilities. In our first study, we …
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Functionalized single-walled carbon nanotubes for composite applications and radiation studies
… be strong, lightweight, and be multifunctional. Single-walled carbon nanotubes (SWNTs) have various properties that fit these criteria as a novel material for space and biomedical applications. To utilize SWNTs for this purpose, new chemical functionalization schemes need to be developed and …
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Optical spectroscopy of single-walled carbon nanotubes in high magnetic fields
Magnetic flux threading a single-walled carbon nanotube (SWNT) is predicted to influence its electronic structure through the Aharonov-Bohm (AB) effect, causing bandgap oscillations and absorption peaks splitting. In order to verify these predictions, near infrared (NIR) photoluminescence (PL) and …
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Mechanical reinforcement of polyacrylamide hydrogels using pristine single-walled carbon nanotubes
… fabricated reinforced PAAm hydrogels using single-walled carbon nanotubes as reinforcing materials. The fusion of SWCNTs and the PAAm matrix successfully generated SWCNTs/PAAm hybrid gels with improved mechanical strength. Moreover, the aqueous dispersion of SWCNTs used for engineering the …
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Adsorption Properties of Single -Walled Carbon Nanotubes for Air Quality Engineering
The adsorption capacities of nanotubes were also determined for pure organic vapors, water vapor and mixtures of organic and water vapor. Adsorption of organic vapors depended mainly on the sample morphology with a maximum uptake equivalent to only ≈50% of the total pore volume of the sample. …
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Temperature effects on the electronic conductivity of single-walled carbon nanotubes
… of conductivity were measured for samples of carbon nanotubes of three types: pristine; functionalized with a nitrobenzene covalent functionalization, which are expected to display poor electronic conductivity; and functionalized with a carbene covalent functionalization, which are expected to …
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Synthesis and electronic transport in single-walled carbon nanotubes of known chirality
Since their discovery in 1991, carbon nanotubes have proven to be a very interesting material for its physical strength, originating from the pure carbon lattice and strong covalent sp2 orbital bonds, and electronic properties which are derived from the lattice structure lending itself to either a …
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Preparation and Characterization of Single Walled Carbon Nanotubes Poly(3-hexylthiophene) Nanohybrids
In this work a purification method for carbon nanotubes was first developed. Purified nanotubes were characterized by AFM, TGA, RAMAN, NIR-PL and then used to prepare composite materials in conjunction with semiconducting polymers. Electrical and optical properties of this composite material were …
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High Performance Electronics Based on Aligned Arrays of Single Walled Carbon Nanotubes
… these components we have built the first carbon nanotube radio. These results represent important first steps to practical implementation of SWNTs in high speed analog circuits.
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Integration of aligned arrays of single-walled carbon nanotubes in electronic devices
Aligned arrays of single-walled carbon nanotubes (SWNTs) are an attractive format for macroelectronics and RF analog electronics with exceptional electrical, mechanical and optical properties. Unlike isolated SWNT, the presence of many SWNTs in the aligned arrays increases the current output and …
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