Provided are a method for directly preparing expanded graphite or graphene under normal temperature and normal pressure, a graphene material, and a product. The method comprises the following specific steps: firstly dispersing graphite in an acidic medium containing an oxidizing agent, and then enabling obtained suspension liquid to stand under normal temperature and normal pressure, thus obtaining expanded graphite. The method does not involve any high-temperature high-pressure reaction process, is safe in operation, low in energy consumption and high in efficiency, and is environmentally-friendly. Obtained expanded graphite can realize 50-1500 times of volume expansion, and an sp2 hybridization structure of a graphene sheet layer is basically not damaged; and the obtained expanded graphite can be widely applied to the fields of energy storage, heat management, photoelectronic devices, solar cells, anti-corrosive materials, various composite materials, and the like. The prepared expanded graphite can also be used as a precursor for preparing high-quality graphene, and the high-quality graphene basically containing no defects can be obtained by peeling off the expanded graphite.

Functionalized graphene sheets having a carbon to oxygen molar ratio of at least about 23:1, an apparatus for preparing the same, and method of preparing the same using the apparatus.

A method for the manufacture of graphene oxide from Kish graphite including the pretreatment of kish graphite and the oxidation of pre-treated kish graphite into graphene oxide, the graphene oxide obtained with at least 45% by weight of oxygen functional groups and the use of the graphene oxide.

Graphite oxide, graphene oxide, and reduced graphene oxide are provided. The graphene oxide includes 25 to 45 at % of oxygen (O) and is effectively exfoliated from graphite oxide, and can embody excellent powder conductivity after reduction.

Provided is a composite substrate which is provided with: a single crystal silicon carbide thin film 11 having a thickness of 1?m or less; a handle substrate 12 which supports the single crystal silicon carbide thin film 11 and is formed from a heat-resistant material (excluding single crystal silicon carbide) having a heat resistance of not less than 1,100? C.; and an intervening layer 13 which has a thickness of 1?m or less and is arranged between the single crystal silicon carbide thin film 11 and the handle substrate 12, and which is formed from at least one material selected from among silicon oxide, silicon nitride, aluminum oxide, aluminum nitride, zirconium oxide, silicon and silicon carbide, or from at least one metal material selected from among Ti, Au, Ag, Cu, Ni, Co, Fe, Cr, Zr, Mo, Ta and W. This composite substrate according to the present invention enables the formation of a nanocarbon film having few defects at low cost.

Functionalized graphene sheets having a carbon to oxygen molar ratio of at least about 23:1 and method of preparing the same.

A coating comprising silicon-doped graphene layers wherein the graphene is in the form of horizontally-aligned graphene nanosheets.

Disclosed is a functionalized graphene containing two or more amines having excellent electrical, thermal and mechanical properties by allowing good interfacial bonding force and uniform dispersion with a thermoplastic polymer, and a method for preparing the functional graphene. The functionalized graphene comprises a carbon material selected from the group consisting of graphene, reduced graphene, graphene oxide, and mixture thereof; and a monovalent amine group and a bivalent or higher amine group which are bonded to the carbon material.

A method for the manufacture of reduced graphene oxide from Kish graphite including the pretreatment of kish graphite, the oxidation of pre-treated kish graphite into graphene oxide and the reduction of graphene oxide into reduced graphene oxide, the reduced graphene oxide and the use of the graphene oxide.

The invention provides a method for preparing graphene which method comprises the steps of: (a) forming a graphite/water mixture; and (b) introducing the graphite/water mixture into a cavitation reactor using at least two offset nozzles; a cavitation reactor for use in the method wherein the cavitation reactor has a cavitation chamber wherein the cavitation chamber has at least two offset inlet nozzles which are directed towards the centre of the cavitation chamber and at least one outlet; and graphene having a carbon content of at least about 98 wt %.