Carbon nanostructures are synthesized from a feedstock that includes polyethylene terephthalate. In a first furnace, the feedstock that includes polyethylene terephthalate and calcium oxide (CaO) or calcium hydroxide (Ca(OH).sub.2) are pyrolyzed to obtain one or more gaseous decomposition products. The gaseous decomposition productions are optionally filtered to remove any solid particles. The one or more gaseous decomposition products are passed across a stainless steel substrate in a second furnace to form the carbon nanostructures.

Carbon nanostructures are synthesized from a feedstock that includes polyethylene terephthalate. In a first furnace, the feedstock that includes polyethylene terephthalate and calcium oxide (CaO) or calcium hydroxide (Ca(OH).sub.2) are pyrolyzed to obtain one or more gaseous decomposition products. The gaseous decomposition productions are optionally filtered to remove any solid particles. The one or more gaseous decomposition products are passed across a stainless steel substrate in a second furnace to form the carbon nanostructures.

Disclosed here is a method of fabricating a covalently reinforced carbon nanotube (CNT) assembly. The method includes producing a CNT assembly by pulling entangled CNTs from a CNT array fabricated on a substrate, the CNT assembly including a plurality of CNTs that are aligned; and creating covalent bonding between the CNTs of the CNT assembly by applying a high energy ion irradiation to the CNT assembly.

Disclosed here is a method of fabricating a covalently reinforced carbon nanotube (CNT) assembly. The method includes producing a CNT assembly by pulling entangled CNTs from a CNT array fabricated on a substrate, the CNT assembly including a plurality of CNTs that are aligned; and creating covalent bonding between the CNTs of the CNT assembly by applying a high energy ion irradiation to the CNT assembly.

A method for obtaining metallic carbon nanotubes is provided. An insulating substrate comprising hollow portions and non-hollow portions is provided. A plurality of electrodes is formed on a surface of the non-hollow portions. A plurality of carbon nanotubes is formed on a surface of the insulating substrate, and the carbon nanotubes stretch across the hollow portions. The insulating substrate, the plurality of electrodes and the carbon nanotubes are placed into a cavity, and the cavity is evacuated. A voltage is applied between any two electrodes, and photos of carbon nanotubes suspended between the two electrodes are taken. In the photo, darker ones are semiconducting carbon nanotubes, and brighter ones are metallic carbon nanotubes. Finally, the semiconducting carbon nanotubes are removed.

A method for obtaining metallic carbon nanotubes is provided. An insulating substrate comprising hollow portions and non-hollow portions is provided. A plurality of electrodes is formed on a surface of the non-hollow portions. A plurality of carbon nanotubes is formed on a surface of the insulating substrate, and the carbon nanotubes stretch across the hollow portions. The insulating substrate, the plurality of electrodes and the carbon nanotubes are placed into a cavity, and the cavity is evacuated. A voltage is applied between any two electrodes, and photos of carbon nanotubes suspended between the two electrodes are taken. In the photo, darker ones are semiconducting carbon nanotubes, and brighter ones are metallic carbon nanotubes. Finally, the semiconducting carbon nanotubes are removed.

Provided is a conductive material dispersion liquid that can reduce internal resistance of a secondary battery while also ensuring good high-temperature storage characteristics of the secondary battery. The conductive material dispersion liquid contains a carbon material, a dispersant, and a dispersion medium. An HSP distance (R.sub.d) of Hansen solubility parameters (HSP.sub.c) of the carbon material and Hansen solubility parameters (HSP.sub.d) of the dispersant is 10.0 MPa.sup.1/2 or less.

Systems and methods for eliminating carbon dioxide and capturing solid carbon are disclosed. By eliminating carbon dioxide gas, e.g., from an effluent exhaust stream of a fossil fuel fired electric power production facility, the inventive concepts presented herein represent an environmentally-clean solution that permanently eliminates greenhouse gases while at the same time producing captured solid carbon products that are useful in various applications including advanced composite material synthesis (e.g., carbon fiber, 3D graphene) and energy storage (e.g., battery technology). Capture of solid carbon during the disclosed process for eliminating greenhouse gasses avoids the inefficiencies and risks associated with conventional carbon dioxide sequestration. Colocation of the disclosed reactor with a fossil fuel fired power production facility brings to bear an environmentally beneficial, and financially viable approach for permanently capturing vast amounts of solid carbon from carbon dioxide gas and other greenhouse gases that would otherwise be released into Earth's biosphere.

The invention discloses equipment and preparation method for open and continuous growth of a carbon nanomaterial. The equipment comprises a metal foil tape feeding system, a CVD system and a collection system. The method includes continuously conveying a metal foil tape pretreated or not into the CVD system via the metal foil tape feeding system, depositing a required carbon nanomaterial on the surface of the metal foil tape by CVD, directly collecting by the collection system or directly post-treating the carbon nanomaterial by a post-treatment system, and even directly producing a end product of the carbon nanomaterial. All the systems in the invention are arranged in the open atmosphere rather than an air-isolated closed space. The invention can realize round-the-clock continuous operation to greatly improve the production efficiency of carbon nanomaterials.

A method of producing advanced carbon materials can include providing coal to a processing facility, beneficiating the coal to remove impurities from the coal, processing the beneficiated coal to produce a pitch, and treating the pitch to produce an advanced carbon material such as carbon fibers, carbon nanotubes, graphene, resins, polymers, biomaterials, or other carbon materials.