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Single-walled carbon nanotubes (SWCNTs) with varying degrees of disorder were investigated using multiple-excitation Raman spectroscopy. The lattice disorder was imparted into the nanotubes by the addition of varying amounts of sulfur to the iron catalyst in a thermal chemical vapor deposition process. Changes in the intensities of peaks occurring due to a double resonance Raman process were studied...
Ablation of needled carbon/carbon (C/C) composite nozzle-throats was studied by hot-fire testing in a small solid rocket motor. The composition of the combustion gases was estimated by principle of free energy minimum. The ablation morphology was investigated by scanning electron microscopy. The ablation mechanism of C/C composites was also studied. The results showed that the ablation performance...
Fuel-cell electrode catalysts with improved electrochemical properties have been prepared by dispersing Pt nanoparticles onto carbon nanotubes (CNT) using a chemical vapor deposition (CVD) method. (Trimethyl)methylcyclopentadienyl platinum (MeCpPtMe 3 ) has been used as a Pt precursor in the CVD process and the CVD conditions have been optimized to disperse small Pt particles onto the CNT...
In this work we report a covalent functionalization of pristine single-walled carbon nanotubes (SWCNTs) directly with three sugar azides, 2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyl, 2,3,4,6-tetra-O-acetyl-β-d-galactopyranosyl or 2,3,4,6-tetra-O-acetyl-β-d-mannopyranosyl azide. Microwave-assisted functionalization was carried out for SWCNTs prepared with the HiPCO method. The as-prepared, new type of...
Anisotropic electrical conduction measurements have been carried out for thin films of vertically-aligned single-walled carbon nanotubes (VA-SWCNTs) grown by an alcohol catalytic CVD process. Combined with controlled synthesis and structure characterization by optical spectroscopy, the influence of the aligned structure on the electrical conduction has been identified. The out-of-plane conductivity...
The dependence of the macroscopic shape of pure carbon on the precursor structure is observed using Reactions under Autogenic Pressure at Elevated Temperatures (RAPET) for the thermal dissociation of several precursors, including stearic acid, oleic acid, linoleic acid, methyl 3 butenoate, methyl butyrate, octadecane, octadecene, octane, octene and acrolein. The precursors are dissociated under their...
Atomic layer deposition (ALD) was used to synthesize metal oxide-carbon nanotube (MO-CNT) hybrid materials by coating nitrogen-doped CNTs (N-CNTs). SnO 2 -CNT hybrids were produced using SnCl 4 and water as precursors and exhibited many unique features. It was demonstrated that the use of N-CNTs was beneficial for directly initiating the ALD of SnO 2 (ALD-SnO 2 ) and...
A relatively simple method to determine the length distribution of carbon nanotubes (CNTs) before and after melt processing was developed. This involves the selection of a suitable solvent for dispersing pristine CNTs as well as to dissolve the matrix of melt mixed composites and the choice of an appropriate nanotube concentration. The length of suitably individualized CNTs was visualized using transmission...
A single-walled carbon nanotube (SWCNT) film was formed on a glass substrate by using the dip-coating method and the resulting material used as a transparent glass heater. The heaters have an optical transparency above 95% in visible light. Their performance was investigated by measuring their heating/cooling characteristics and thermal resistance. They have a heating performance that is ∼70% higher...
Amorphous carbon nanotubes (a-CNTs) were synthesized by a simple process using ammonium chloride and ferrocene at a low temperature (∼250°C) in open atmosphere. The as-prepared samples were oxidized by a simple acid treatment and further functionalized with stearic acid. For the confirmation of oxidation and functionalization, the pristine and the modified a-CNTs were characterized by Fourier transformed...
We have encapsulated adamantane (C 10 H 16 ) in single- and multi-walled carbon nanotubes. Adamantane is a high symmetry cage like molecule with point group symmetry T d and can be considered as a hydrogen-terminated diamond fragment. We confirmed and identified the successful filling by high resolution transmission electron microscopy, 13 C nuclear magnetic resonance,...
The objective of the present study is to investigate temperature and chemical sensitivity of carbon nanofilms made on diamond surface by high temperature surface modification followed by plasma treatment. The carbon nanofilms made this way were characterized by electrical measurements, Raman spectroscopy and atomic force microscopy. The nanofilms were found amorphous in nature. They showed significant...
A method was developed to visualize each SWCNT in an array under an optical microscope. By decorating the SWCNTs with gold nanoparticles of controlled size and density with a seeded electroless deposition process, the SWCNTs become visible under ordinary optical microscope. The visibility of the gold-decorated SWCNT is the result of coupled surface plasmon resonance adsorption of the dense gold nanoparticles...
Mesophase pitch based graphite foams with different thermal properties and cell structures were infiltrated with glass by pressureless infiltration to prepare potential alternative composites for cooling electronics. Microstructure, thermal diffusivity and coefficient of thermal expansion (CTE) of the obtained composites were investigated. It was demonstrated that there was excellent wettability of...
Homogenous organic dispersion of graphene oxide (GO) sheets was prepared by a solvent-exchange method. This method enabled the simultaneous achievement of full exfoliation and high concentration of GO in several organic solvents such as dimethyl sulfoxide, which would facilitate the fabrication of individual graphene reinforced polymer composites through a solution-based process. To this end, poly...
High specific surface carbon (Black Pearls 2000) has been modified by electroactive anthraquinone (AQ) groups by spontaneous reduction of the corresponding in situ generated diazonium derivative. A set of modified carbons with different AQ loadings have been synthesized to study the effect of the grafted groups on the pore texture and on the double layer capacitance of the modified carbons. Grafting...
Mesoporous carbon spheres with hierarchical foam-like pore structures have been synthesized by a dual-templating strategy using phenolic resol as a carbon source, Pluronic F127 and spherical silica mesocellular foams (Si-MCFs) as the soft and hard template, respectively. The results show that the morphology and mesostructure of the silica template are faithfully replicated. The obtained mesoporous...
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