We demonstrate the efficient chemical vapor deposition synthesis of single-walled carbon nanotubes where activity and lifetime catalysts are enhanced by water. Water-stimulated catalytic results in massive growth superdense vertically aligned nanotube forests with heights up to 2.5 millimeters that can be easily separated from catalysts, providing material purity above 99.98%. Moreover, patterned, highly organized intrinsic structures were successfully fabricated. The water-assisted method...

By using an ionic liquid of 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, we uniformly dispersed single-walled carbon nanotubes (SWNTs) as chemically stable dopants in a vinylidene fluoride-hexafluoropropylene copolymer matrix to form composite film. We found that the SWNT content can be increased up 20 weight percent without reducing mechanical flexibility or softness copolymer. The film was coated with dimethyl-siloxane-based rubber, which exhibited conductivity 57...

Among all known materials, we found that a forest of vertically aligned single-walled carbon nanotubes behaves most similarly to black body, theoretical material absorbs incident light. A requirement for an object behave as body is perfectly absorb light wavelengths. This important feature has not been observed real materials because intrinsically have specific absorption bands their structure and composition. We can almost across very wide spectral range (0.2-200 mum). attribute this...

Supercapacitor electrodes fabricated from single-walled carbon nanotubes (SWNTs) are shown to be capable of durable operation at 4 V, exceeding the operating voltage limit activated (AC, 3 V), while delivering significantly higher energy and power (see figure). Dual exploitation SWNTs as combined current collectors is also explored.

Increased portability, versatility and ubiquity of electronics devices are a result their progressive miniaturization, requiring current flow through narrow channels. Present-day operate close to the maximum current-carrying-capacity (that is, ampacity) conductors (such as copper gold), leading decreased lifetime performance, creating demand for new with higher ampacity. Ampacity represents current-carrying capacity object that depends both on structure material. Here we report carbon...

Thermoelectrics is a challenging issue for modern and future energy conversion recovery technology. Carbon nanotubes are promising active thermoelectic materials owing to their narrow bandgap high charge carrier mobility they can be integrated into flexible thermoelectrics that recover any waste heat. We here report air-stable n-type single walled carbon with variety of weak electron donors in the range HOMO level between ca. −4.4 eV −5.6 eV, which partial uphill injection from dopant...

Viscoelasticity describes the ability of a material to possess both elasticity and viscosity. Viscoelastic materials, such as rubbers, limited operational temperature range (for example, for silicone rubber it is -55° 300°C), above which breaks down below undergoes glass transition hardens. We created viscoelastic composed from random network long interconnected carbon nanotubes that exhibited an -196° 1000°C. The storage loss moduli, frequency stability, reversible deformation level,...

Electrostatic flocking is applied to create an array of aligned carbon fibers from which elastomeric thermal interface material (TIM) can be fabricated with a high through-plane conductivity 23.3 W/mK. A achieved significantly low filler level (13.2 wt%). As result, this retains the intrinsic properties matrix, i.e., behavior. service our authors and readers, journal provides supporting information supplied by authors. Such materials are peer reviewed may re-organized for online delivery,...

A novel composite is presented as a supercapacitor electrode with high maximum power rating (990 kW/kg; 396 kW/l) exceeding performances of other electrodes. The high-power capability the stemmed from its unique meso-macro pore structure engineered through utilization single-walled carbon nanotubes (20 wt %) scaffolding for nanohorns (80 %). also exhibited durable operation (6.5% decline in capacitance over 100 000 cycles) result monolithic chemical composition and mechanical stability. was...

Here we investigate the kinetics of water-assisted CVD (henceforth denoted as supergrowth CVD) by a quantitative time-evolution analysis based on simple growth model. We found that can be well described model where dynamics catalyst activity is treated similar to radioactive decay. An in-depth this revealed CVD, showing scale relationship between carbon source and water, elucidated role water enhancer preserver.

We propose a statistical and macroscopic analysis to estimate the catalyst activity of water-assisted growth (super-growth) single-walled nanotubes (SWNT) characterize SWNT forests. The was estimated be 84% (+/-6%), highest ever reported. forest found very sparse material where SWNTs represent only 3.6% total volume. This structural sparseness is believed play critical role in achieving highly efficient growth.

Ionic liquids allow millimeter-long single-walled carbon nanotubes to associate tightly, forming a free-standing sheet with superb mechanical and electrical properties. An actuator strip, fabricated by sandwiching an ionic-liquid-gel electrolyte layer the sheets obtained exhibits large deformation in quick response (4 mm per 0.05 s) low applied voltages, high durability upon 10 000 times continuous operations. Detailed facts of importance specialist readers are published as "Supporting...

Nanostructured carbons have been widely used for fabricating enzyme-modified electrodes due to their large specific surface area. However, because they are random aggregates of particular or tubular nanocarbons, the postmodification enzymes intrananospace is generally hard control. Here, we describe a free-standing film carbon nanotube forest (CNTF) that can form hybrid ensemble with through liquid-induced shrinkage. This provides in situ regulation its (inter-CNT pitch) size and eventually...

The dispersion of silica nanoparticles made an ionic liquid, 1-ethyl-3-methyl imidazolium bis(trifluoromethanesulfonyl)amide ([C(2)mim][NTf(2)]), gelled even by the addition 2-3 wt %, due to formation interconnected particulate networks in [C(2)mim][NTf(2)]. transport and viscoelastic properties these nanocomposite ion gels were investigated relation microstructure. Despite their solid-like behavior, exhibited a high conductivity approximately 10(-2) S cm(-1) at 30 degrees C, which is...

We elucidated the secret of water-assisted chemical vapor deposition (CVD) by elucidating influence water on catalysts, through ex situ microscopic and spectroscopic analysis. unambiguously showed that catalyst deactivation readily occurs due to carbon coating acted remove this revive catalysts activity. This represents central point CVD.

Resonance Raman scattering is used to determine the radial breathing mode (RBM) frequency $({\ensuremath{\omega}}_{\text{RBM}})$ dependence on tube diameter $({d}_{t})$ for single-wall carbon nanotubes (SWNTs). We establish experimentally ${\ensuremath{\omega}}_{\text{RBM}}=227.0/{d}_{t}$ as fundamental relation pristine SWNTs. All other RBM values found in literature can be explained by an upshift due mostly van der Waals interaction between SWNTs and environment.

Here, we report a highly efficient growth of single-walled carbon nanotubes (SWNTs) and double-walled (DWNTs) on conducting metal foils. We found that foils made Ni-based alloys with Cr or Fe serve as excellent substrates for SWNT (DWNT) synthesis. In significant contrast, CNT grown Ni, contains ratio MWNTs. This result opens up an economical route the mass production forests also enables straightforward integration CNTs into nanoelectronic devices, such field emission displays.

Alignment represents an important structural parameter of carbon nanotubes (CNTs) owing to their exceptionally high aspect ratio, one-dimensional property. In this paper, we demonstrate a general approach control the alignment few-walled CNT forests from nearly random ideally aligned by tailoring density active catalysts at catalyst formation stage, which can be experimentally achieved controlling forest mass density. Experimentally, found that and degree were inseparably linked because...

Abstract An approach is presented to make a “surface‐only solid” with surface area of 2 240 m g −1 (1 310 cm −3 ), corresponding 85% the atoms constituting surface, by opening single‐walled carbon nanotube forests and solids via controlled oxidation. The controllability demonstrated tailoring hole size match guest molecule, for example, nitrogen, fullerene, or solvated ions. These features surface‐only solid an ideal vessel material energy storage, as its use electrodes realize light compact...

Substantial progress on field effect transistors (FETs) consisting of semiconducting single wall carbon nanotubes (s-SWNTs) without detectable traces metallic and impurities is reported. Nearly perfect removal confirmed by optical absorption, Raman measurements, electrical measurements. This outstanding result was made possible in particular ultracentrifugation (150000g) solutions prepared from SWNT powders using polyfluorene as an extracting agent toluene. Such s-SWNTs processable were...