Browsing by Author "Nikolaev, Pavel"

Now showing 1 - 20 of 42
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    Array of fullerene nanotubes
    (2009-12-15) Smalley, Richard E.; Colbert, Daniel T.; Dai, Hongjie; Liu, Jie; Rinzler, Andrew G.; Hafner, Jason H.; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    This invention relates generally to forming an array of fullerene nanotubes. In one embodiment, a macroscopic molecular array is provided comprising at least about 106 fullerene nanotubes in generally parallel orientation and having substantially similar lengths in the range of from about 5 to about 500 nanometers.
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    Array of single-wall carbon nanotubes
    (2006-07-04) Smalley, Richard E.; Colbert, Daniel T.; Dai, Hongjie; Liu, Jie; Rinzler, Andrew G.; Hafner, Jason H.; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    This invention relates generally to forming an array of single-wall carbon nanotubes (SWNT). In one embodiment, a macroscopic molecular array is provided comprising at least about 106 single-wall carbon nanotubes in generally parallel orientation and having substantially similar lengths in the range of from about 5 to about 500 nanometers.
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    Carbon fibers formed from single-wall carbon nanotubes
    (2004-01-27) Smalley, Richard E.; Colbert, Daniel T.; Dai, Hongjie; Liu, Jie; Rinzler, Andrew G.; Hafner, Jason H.; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    A method for purifying a mixture comprising single-wall carbon nanotubes and amorphous carbon contaminate is disclosed. The method includes the steps of heating the mixture under oxidizing conditions sufficient to remove the amorphous carbon, followed by recovering a product comprising at least about 80% by weight of single-wall carbon nanotubes. A method for producing tubular carbon molecules of about 5 to 500 nm in length is also disclosed. The method includes the steps of cutting single-wall nanotube containing-material to form a mixture of tubular carbon molecules having lengths in the range of 5-500 nm and isolating a fraction of the molecules having substantially equal lengths. The nanotubes may be used, singularly or in multiples, in power transmission cables, in solar cells, in batteries, as antennas, as molecular electronics, as probes and manipulators, and in composites.
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    Carbon Nanotubes and Related Nanomaterials: Critical Advances and Challenges for Synthesis toward Mainstream Commercial Applications
    (American Chemical Society, 2018) Rao, Rahul; Pint, Cary L.; Islam, Ahmad E.; Weatherup, Robert S.; Hofmann, Stephan; Meshot, Eric R.; Wu, Fanqi; Zhou, Chongwu; Dee, Nicholas; Amama, Placidus B.; Carpena-Nuñez, Jennifer; Shi, Wenbo; Plata, Desiree L.; Penev, Evgeni S.; Yakobson, Boris I.; Balbuena, Perla B.; Bichara, Christophe; Futaba, Don N.; Noda, Suguru; Shin, Homin; Kim, Keun Su; Simard, Benoit; Mirri, Francesca; Pasquali, Matteo; Fornasiero, Francesco; Kauppinen, Esko I.; Arnold, Michael; Cola, Baratunde A.; Nikolaev, Pavel; Arepalli, Sivaram; Cheng, Hui-Ming; Zakharov, Dmitri N.; Stach, Eric A.; Zhang, Jin; Wei, Fei; Terrones, Mauricio; Geohegan, David B.; Maruyama, Benji; Maruyama, Shigeo; Li, Yan; Adams, W. Wade; Hart, A. John
    Advances in the synthesis and scalable manufacturing of single-walled carbon nanotubes (SWCNTs) remain critical to realizing many important commercial applications. Here we review recent breakthroughs in the synthesis of SWCNTs and highlight key ongoing research areas and challenges. A few key applications that capitalize on the properties of SWCNTs are also reviewed with respect to the recent synthesis breakthroughs and ways in which synthesis science can enable advances in these applications. While the primary focus of this review is on the science framework of SWCNT growth, we draw connections to mechanisms underlying the synthesis of other 1D and 2D materials such as boron nitride nanotubes and graphene.
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    Catalytic growth of single-walled nanotubes by laser vaporization
    (1996) Nikolaev, Pavel; Smalley, Richard E.
    Direct laser vaporization of transition-metal/graphite composite rods produced single-walled carbon nanotubes (SWT) in the condensing vapor in a heated flow tube. A much higher yield of nanotubes was found, with little of the amorphous overcoating on those produced by the metal-catalyzed arc-discharge method. A number of parameters were varied to achieve the highest yield. A mixture of Co with Ni catalyzed about 50% of all the carbon vaporized to SWT. A model for SWT growth is presented for both the present case and the arc.
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    Continuous fiber of fullerene nanotubes
    (2010-02-02) Smalley, Richard E.; Colbert, Daniel T.; Dai, Hongjie; Liu, Jie; Rinzler, Andrew G.; Hafner, Jason H.; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    This invention relates generally to carbon fiber produced from fullerene nanotube arrays. In one embodiment, the present invention involves a macroscopic carbon fiber comprising at least 106 fullerene nanotubes in generally parallel orientation.
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    Continuous fiber of single-wall carbon nanotubes
    (2005-12-27) Smalley, Richard E.; Colbert, Daniel T.; Dai, Hongjie; Liu, Jie; Rinzler, Andrew G.; Hafner, Jason H.; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    This invention relates generally to carbon fiber produced from single-wall carbon nanotube (SWNT) molecular arrays. In one embodiment, the present invention involves a macroscopic carbon fiber comprising at least 106 signal-wall carbon nanotubes in generally parallel orientation.
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    Electrical conductors comprising single-wall carbon nanotubes
    (2005-11-29) Smalley, Richard E.; Colbert, Daniel T.; Guo, Ting; Rinzler, Andrew G.; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    The present invention concerns electrical conductors comprising armchair single-wall carbon nanotubes. Such electrical conductors made by the invention are metallic, i.e., they will conduct electrical charges with a relatively low resistance. The amount of armchair single-wall carbon nanotubes in the electrical conductor can be greater than 10%, greater than 30%, greater than 50%, greater than 75%, and greater than 90%, of the single-wall carbon nanotubes in the electrical conductor.
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    Enhancement of the Electron Spin Resonance of Single-Walled Carbon Nanotubes by Oxygen Removal
    (American Chemical Society, 2012) Rice, William D.; Weber, Ralph T.; Leonard, Ashley D.; Tour, James M.; Nikolaev, Pavel; Arepalli, Sivaram; Berka, Vladimir; Tsai, Ah-Lim; Kono, Junichiro
    We have observed a nearly 4-fold increase in the electron spin resonance (ESR) signal from an ensemble of single-walled carbon nanotubes (SWCNTs) due to oxygen desorption. By performing temperature-dependent ESR spectroscopy both before and after thermal annealing, we found that the ESR in SWCNTs can be reversibly altered via the molecular oxygen content in the samples. Independent of the presence of adsorbed oxygen, a Curie law (spin susceptibility ∝ 1/T) is seen from ∼4 to 300 K, indicating that the probed spins are finite-level species. For both the pre-annealed and post-annealed sample conditions, the ESR line width decreased as the temperature was increased, a phenomenon we identify as motional narrowing. From the temperature dependence of the line width, we extracted an estimate of the intertube hopping energy; for both sample conditions, we found this hopping energy to be ∼1.2 meV. Since the spin hopping energy changes only slightly when oxygen is desorbed, we conclude that only the spin susceptibility, not spin transport, is affected by the presence of physisorbed molecular oxygen in SWCNT ensembles. Surprisingly, no line width change is observed when the amount of oxygen in the SWCNT sample is altered, contrary to other carbonaceous systems and certain 1D conducting polymers. We hypothesize that physisorbed molecular oxygen acts as an acceptor (p-type), compensating the donor-like (n-type) defects that are responsible for the ESR signal in bulk SWCNTs.
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    Enhancement of the Electron Spin Resonance of Single-Walled Carbon Nanotubes by Oxygen Removal
    (American Chemical Society, 2012) Rice, William D.; Weber, Ralph T.; Leonard, Ashley D.; Tour, James M.; Nikolaev, Pavel; Arepalli, Sivaram; Berka, Vladimir; Tsai, Ah-Lim; Kono, Junichiro
    We have observed a nearly 4-fold increase in the electron spin resonance (ESR) signal from an ensemble of single-walled carbon nanotubes (SWCNTs) due to oxygen desorption. By performing temperature-dependent ESR spectroscopy both before and after thermal annealing, we found that the ESR in SWCNTs can be reversibly altered via the molecular oxygen content in the samples. Independent of the presence of adsorbed oxygen, a Curie law (spin susceptibility ∝ 1/T) is seen from ∼4 to 300 K, indicating that the probed spins are finite-level species. For both the pre-annealed and post-annealed sample conditions, the ESR line width decreased as the temperature was increased, a phenomenon we identify as motional narrowing. From the temperature dependence of the line width, we extracted an estimate of the intertube hopping energy; for both sample conditions, we found this hopping energy to be ∼1.2 meV. Since the spin hopping energy changes only slightly when oxygen is desorbed, we conclude that only the spin susceptibility, not spin transport, is affected by the presence of physisorbed molecular oxygen in SWCNT ensembles. Surprisingly, no line width change is observed when the amount of oxygen in the SWCNT sample is altered, contrary to other carbonaceous systems and certain 1D conducting polymers. We hypothesize that physisorbed molecular oxygen acts as an acceptor (p-type), compensating the donor-like (n-type) defects that are responsible for the ESR signal in bulk SWCNTs.
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    Fullerene nanotube compositions
    (2008-06-24) Smalley, Richard E.; Colbert, Daniel T.; Dai, Hongjie; Liu, Jie; Rinzler, Andrew G.; Hafner, Jason H.; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    This invention relates generally to a fullerene nanotube composition. The fullerene nanotubes may be in the form of a felt, such as a bucky paper. Optionally, the fullerene nanotubes may be derivatized with one or more functional groups. Devices employing the fullerene nanotubes of this invention are also disclosed.
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    Gas phase production of single-walled carbon nanotubes
    (2000) Nikolaev, Pavel; Smalley, Richard E.
    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 decomposition of iron pentacarbonyl. The yield of nanotubes and their diameter distribution can be varied by varying process parameters: nanotubes as small as 0.6 nm in diameter, corresponding to the size of a C60 molecule, have been generated. This process shows great promise for scaling up for bulk production of carbon nanotubes.
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    Gas-phase nucleation and growth of single-wall carbon nanotubes from high pressure CO
    (2004-07-13) Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Nikolaev, Pavel; Bronikowski, Michael J.; Bradley, Robert K.; Rohmund, Frank; Rice University; United States Patent and Trademark Office
    The present invention discloses the process of supplying high pressure (e.g., 30 atmospheres) CO that has been preheated (e.g., to about 1000° C.) and a catalyst precursor gas (e.g., Fe(CO)5) in CO that is kept below the catalyst precursor decomposition temperature to a mixing zone. In this mixing zone, the catalyst precursor is rapidly heated to a temperature that results in (1) precursor decomposition, (2) formation of active catalyst metal atom clusters of the appropriate size, and (3) favorable growth of SWNTs on the catalyst clusters. Preferably a catalyst cluster nucleation agency is employed to enable rapid reaction of the catalyst precursor gas to form many small, active catalyst particles instead of a few large, inactive ones. Such nucleation agencies can include auxiliary metal precursors that cluster more rapidly than the primary catalyst, or through provision of additional energy inputs (e.g., from a pulsed or CW laser) directed precisely at the region where cluster formation is desired. Under these conditions SWNTs nucleate and grow according to the Boudouard reaction. The SWNTs thus formed may be recovered directly or passed through a growth and annealing zone maintained at an elevated temperature (e.g., 1000° C.) in which tubes may continue to grow and coalesce into ropes.
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    Macroscopically manipulable nanoscale devices made from nanotube assemblies
    (2006-05-23) Colbert, Daniel T.; Dai, Hongjie; Hafner, Jason H.; Rinzler, Andrew G.; Smalley, Richard E.; Liu, Jie; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    Macroscopically manipulable nanoscale devices made from nanotube assemblies are disclosed. The article of manufacture comprises a macroscopic mounting element capable of being manipulated or observed in a macroscale environment, and a nanoscale nanotube assembly attached to the mounting element. The article permits macroscale information to be provided to or obtained from a nanoscale environment. A method for making a macroscopically manipulable nanoscale devices comprises the steps of (1) providing a nanotube-containing material; (2) preparing a nanotube assembly device having at least one carbon nanotube for attachment; and (3) attaching said nanotube assembly to a surface of a mounting element.
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    Macroscopically manipulable nanoscale devices made from nanotube assemblies
    (2011-06-14) Colbert, Daniel T.; Dai, Hongjie; Hafner, Jason H.; Rinzler, Andrew G.; Smalley, Richard E.; Liu, Jie; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    This invention relates generally to cutting single-wall carbon nanotubes (SWNT). In one embodiment, the present invention provides for preparations of homogeneous populations of short carbon nanotube molecules by cutting and annealing (reclosing) the nanotube pieces followed by fractionation. The cutting and annealing processes may be carried out on a purified nanotube bucky paper, on felts prior to purification of nanotubes or on any material that contains single-wall nanotubes. In one embodiment, oxidative etching with concentrated nitric acid is employed to cut SWNTs into shorter lengths. The annealed nanotubes may be disbursed in an aqueous detergent solution or an organic solvent for the fractionation. Closed tubes can also be derivatized to facilitate fractionation, for example, by adding solubilizing moieties to the end caps.
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    Membrane comprising an array of single-wall carbon nanotubes
    (2007-04-17) Smalley, Richard E.; Colbert, Daniel T.; Dai, Hongjie; Liu, Jie; Rinzler, Andrew G.; Hafner, Jason H.; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    This invention relates generally to membranes comprising an array of single-wall carbon nanotubes (SWNT) wherein the membrane is nanoporous. In one embodiment, the membrane comprises a substantially two-dimensional array of a homogeneous population of single-walled nanotubes aggregated in substantially parallel orientation to form a monolayer extending in directions substantially perpendicular to the orientation of the individual nanotubes. Using single-wall carbon nanotubes of the same type and structure provides a homogeneous array. By using different single-wall carbon nanotubes, either a random or ordered heterogeneous structure can be produced by employing successive reactions after removal of previously masked areas of a substrate. Other embodiments of the invention include batteries comprising a membrane comprising an array of single-wall carbon nanotubes or carbon fibers that are aggregates of single-wall carbon nanotubes, and wherein the plurality of single-wall carbon nanotubes are in a generally parallel orientation.
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    Method for cutting fullerene nanotubes
    (2009-01-27) Smalley, Richard E.; Colbert, Daniel T.; Dai, Hongjie; Liu, Jie; Rinzler, Andrew G.; Hafner, Jason H.; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    This invention relates generally to cutting fullerene nanotubes. In one embodiment, the present invention provides for preparation of homogeneous populations of short fullerene nanotubes by cutting and annealing (reclosing) the nanotube pieces followed by fractionation. The cutting and annealing processes may be carried out on a purified nanotube bucky paper, on felts prior to purification of nanotubes or on any material that contains fullerene nanotubes. In one embodiment, oxidative etching with concentrated nitric acid is employed to cut fullerene nanotubes into shorter lengths. The annealed nanotubes may be disbursed in an aqueous detergent solution or an organic solvent for the fractionation. Closed tubes can also be derivatized to facilitate fractionation, for example, by adding solubilizing moieties to the end caps.
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    Method for cutting nanotubes
    (2006-03-07) Smalley, Richard E.; Colbert, Daniel T.; Dai, Hongjie; Liu, Jie; Rinzler, Andrew G.; Hafner, Jason H.; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    This invention relates generally to cutting single-wall carbon nanotubes (SWNT). In one embodiment, the present invention provides for preparation of homogeneous populations of short carbon nanotube molecules by cutting and annealing (reclosing) the nanotube pieces followed by fractionation. The cutting and annealing processes may be carried out on a purified nanotube bucky paper, on felts prior to purification of nanotubes or on any material that contains single-wall nanotubes. In one embodiment, oxidative etching with concentrated nitric acid is employed to cut SWNTs into shorter lengths. The annealed nanotubes may be disbursed in an aqueous detergent solution or an organic solvent for the fractionation. Closed tubes can also be derivatized to facilitate fractionation, for example, by adding solubilizing moieties to the end caps.
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    Method for cutting single-wall carbon nanotubes
    (2006-05-30) Colbert, Daniel T.; Dai, Hongjie; Hafner, Jason H.; Rinzler, Andrew G.; Smalley, Richard E.; Liu, Jie; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    This invention relates generally to cutting single-wall carbon nanotubes (SWNT). In one embodiment, the present invention provides for preparations of homogemeous populations of short carbon nanotube molecules by cutting and annealing (reclosing) the nanotube pieces followed by fractionation. The cutting and annealing processes may be carried out on a purified nanotube bucky paper, on felts prior to purification of nanotubes or on any material that contains single-wall nanotubes. In one embodiment, oxidative etching with concentrated nitric acid is employed to cut SWNTs into shorter lengths. The annealed nanotubes may be disbursed in an aqueous detergent solution or an organic solvent for the fractionation. Closed tubes can also be derivatized to facilitate fractionation, for example, by adding solubilizing moieties to the end caps.
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    Method for forming a patterned array of fullerene nanotubes
    (2009-03-31) Smalley, Richard E.; Colbert, Daniel T.; Dai, Hongjie; Liu, Jie; Rinzler, Andrew G.; Hafner, Jason H.; Smith, Kenneth A.; Guo, Ting; Nikolaev, Pavel; Thess, Andreas; Rice University; United States Patent and Trademark Office
    This invention relates generally to forming a patterned array of fullerene nanotubes. In one embodiment, a nanoscale array of microwells is provided on a substrate; a metal catalyst is deposited in each microwells; and a stream of hydrocarbon or CO feedstock gas is directed at the substrate under conditions that effect growth of fullerene nanotubes from each microwell.