A method for coating a metal workpiece with graphene includes exposing the metal workpiece to a carbon-containing precursor gas and a hydrogen gas in a processing chamber in a first phase, and to the carbon-containing precursor gas, the hydrogen gas and a first carrier gas in the processing chamber in a second phase after the first phase. A first flow rate of the carbon-containing precursor gas into the processing chamber is higher than a second flow rate of the carbon-containing precursor gas into the processing chamber, and a first flow rate of the hydrogen gas into the processing chamber is higher than a second flow rate of the hydrogen gas into the processing chamber. A first total gas pressure in the processing chamber in the first phase is lower than a second total gas pressure in the processing chamber in the second phase.

Provided is a method of producing multiple isolated hollow graphene balls, comprising: (a) mixing multiple particles of a graphitic material and multiple particles of a solid polymer carrier material to form a mixture in an impacting chamber of an energy impacting apparatus; (b) operating the energy impacting apparatus to peel off graphene sheets from the graphitic material and transferring the graphene sheets to surfaces of solid polymer carrier material particles to produce graphene-coated polymer particles; (c) recovering the graphene-coated polymer particles from the impacting chamber; and (d) suspending the graphene-encapsulated polymer particles in a gaseous medium to keep the particles separated from each other while concurrently pyrolyzing the particles to thermally convert polymer into pores and carbon, wherein at least one of the graphene balls comprises a hollow core enclosed by a shell composed of graphene sheets bonded together by carbon.

A method for the production of a graphene layer structure having from 1 to 100 graphene layers, the method comprising providing a substrate having a thermal resistance equal to or greater than that of sapphire, on a heated susceptor in a reaction chamber, the chamber having a plurality of cooled inlets arranged so that, in use, the inlets are distributed across the substrate and have a constant separation from the substrate, supplying a flow comprising a precursor compound through the inlets and into the reaction chamber to thereby decompose the precursor compound and form graphene on the substrate, wherein the inlets are cooled to less than 100° C., preferably 50 to 60° C., and the susceptor is heated to a temperature of at least 50° C. in excess of a decomposition temperature of the precursor, using a laser to selectively ablate graphene from the substrate, wherein the laser has a wavelength in excess of 600 nm and a power of less than 50 Watts.

Embodiments described herein relate generally to the large scale production of functionalized graphene. In some embodiments, a method for producing functionalized graphene includes combining a crystalline graphite with a first electrolyte solution that includes at least one of a metal hydroxide salt, an oxidizer, and a surfactant. The crystalline graphite is then milled in the presence of the first electrolyte solution for a first time period to produce a thinned intermediate material. The thinned intermediate material is combined with a second electrolyte solution that includes a strong oxidizer and at least one of a metal hydroxide salt, a weak oxidizer, and a surfactant. The thinned intermediate material is then milled in the presence of the second electrolyte solution for a second time period to produce functionalized graphene.

Functionally graded graphene materials, methods of making and uses thereof are described.

The embodiments of the present disclosure relate to a method and apparatus for producing a carbon nanomaterial product (CNM) product that may comprise carbon nanotubes and various other allotropes of nanocarbon. The method and apparatus employ a consumable carbon dioxide (CO.sub.2) and a renewable carbonate electrolyte as reactants in an electrolysis reaction in order to make CNTs. In some embodiments of the present disclosure, operational conditions of the electrolysis reaction may be varied in order to produce the CNM product with a greater incidence of a desired allotrope of nanocarbon or a desired combination of two or more allotropes.

Compounds having an elastomer material, a filler material, at least one additive material, and at least one accelerant material are disclosed. In various embodiments, the filler material comprises a graphene-based carbon material. In various embodiments, the graphene-based carbon material comprises graphene comprising up to 15 layers, carbon aggregates having a median size from 1 to 50 microns, a surface area of the carbon aggregates at least 50 m.sup.2/g, when measured via a Brunauer-Emmett-Teller (BET) method with nitrogen as the adsorbate, and no seed particles.

Provided are a cured product containing a single-layer graphene, a single-layer graphene, a preparation method therefor, and an article containing a single-layer graphene. The method for preparing the cured product containing a single-layer graphene includes (a) mixing graphite with a curable material and optionally a first solvent, and curing and molding same to obtain molded granules; (b) heating a system formed by the molded granules and optionally a second solvent, then introducing a gas for pressurization, and then releasing the pressure to obtain expanded granules; and (c) repeating step (a) and (b) several times, with the graphite and the curable material in step (a) replaced with the expanded granules, to obtain a cured product containing a single-layer graphene. The cured product containing a single-layer graphene is carbonized and separated to obtain a single-layer graphene. The article containing a single-layer graphene contains the cured product or the single-layer graphene.

A graphite membrane includes graphene layers, wherein the graphite membrane is an independent graphite membrane having a thickness of 10 nm to 12 μm, an area of 5×5 mm.sup.2 or more, an electrical conductivity of 8000 S/cm or more, and an arithmetic average roughness Ra of 200 nm or less on a surface of the graphite membrane.

Methods for forming a graphene film on a silicon carbide material are provided, along with the resulting coated materials. The method can include: heating the silicon carbide material to a growth temperature (e.g., about 1,000° C. to about 2,200° C.), and exposing the silicon carbide material to a growth atmosphere comprising a halogen species. The halogen species reacts with the silicon carbide material to remove silicon therefrom. The halogen species can comprise fluorine (e.g., SiF.sub.4, etc.), chlorine (e.g., SiCl.sub.4), or a mixture thereof.