Methods of making graphene oxide and reduced graphene oxide are provided. The methods can include a simple one-pot synthesis of graphene oxide from a purified coal powder using a mild oxidizing acid. The methods provide for an improved, more cost-effective, and simpler process than conventional methods such as Hummers methods. In some aspects, placing the purified coal powder in the mild oxidation atmosphere includes contacting the purified coal powder with a mild oxidizing acid such as nitric acid, nitrous acid, sulfuric acid, phosphoric acid, benzoic acid, or a combination thereof. In some aspects, the mild oxidizing acid consists essentially of nitric acid. Graphene oxides and reduced graphene oxides prepared by the methods are also provided.

A porous graphene film, its manufacturing method and an electronic product are provided. The method of manufacturing the porous graphene film includes: mixing a dispersion liquid of graphene with a dispersion liquid of particles, and performing a film-forming process to form a mixed film of graphene and particles; and removing the particles in the mixed film of graphene and particles to form the porous graphene film. The porous graphene film prepared by the method has a large specific surface area and an excellent electroconductivity.

A porous graphene film, its manufacturing method and an electronic product are provided. The method of manufacturing the porous graphene film includes: mixing a dispersion liquid of graphene with a dispersion liquid of particles, and performing a film-forming process to form a mixed film of graphene and particles; and removing the particles in the mixed film of graphene and particles to form the porous graphene film. The porous graphene film prepared by the method has a large specific surface area and an excellent electroconductivity.

The present invention provides an efficient and effective method to produce a graphene material by a high shear mechanical process to exfoliate a natural graphite dispersion in a solvent, followed by supercritical exfoliation and drying. The method exfoliates all graphitic flakes into mostly few-layer graphene flakes. This method is more efficient than traditional mechanical exfoliation techniques and completely avoids the need of multiple sampling/centrifugation cycles. The graphene flakes are generally uniform in both size (area) and thickness and show no clumping or aggregation. After drying, this graphene material has high dispersibility in a suitable solvent; the prepared graphene dispersion is stable for at least three months and shows no indication of settling or separation.

The present invention provides an efficient and effective method to produce a graphene material by a high shear mechanical process to exfoliate a natural graphite dispersion in a solvent, followed by supercritical exfoliation and drying. The method exfoliates all graphitic flakes into mostly few-layer graphene flakes. This method is more efficient than traditional mechanical exfoliation techniques and completely avoids the need of multiple sampling/centrifugation cycles. The graphene flakes are generally uniform in both size (area) and thickness and show no clumping or aggregation. After drying, this graphene material has high dispersibility in a suitable solvent; the prepared graphene dispersion is stable for at least three months and shows no indication of settling or separation.

Provided herein are methods, devices and systems for processing of carbonaceous compositions. The processing may include the manufacture (or synthesis) of oxidized forms of carbonaceous compositions and/or the manufacture (or synthesis) of reduced forms of oxidized carbonaceous compositions. Some embodiments provide methods, devices and systems for the manufacture (or synthesis) of graphite oxide from graphite and/or for the manufacture (or synthesis) of reduced graphite oxide from graphite oxide.

Provided herein are methods, devices and systems for processing of carbonaceous compositions. The processing may include the manufacture (or synthesis) of oxidized forms of carbonaceous compositions and/or the manufacture (or synthesis) of reduced forms of oxidized carbonaceous compositions. Some embodiments provide methods, devices and systems for the manufacture (or synthesis) of graphite oxide from graphite and/or for the manufacture (or synthesis) of reduced graphite oxide from graphite oxide.

A nanocarbon separation device includes a separation tank that is configured to accommodate a dispersion liquid including nanocarbons, a first electrode provided at an upper part in the separation tank, a second electrode provided at a lower part in the separation tank, an evaluation unit that is configured to evaluate a physical state or a chemical state of the dispersion liquid, and a determination unit that is configured to determine a separation state between metallic nanocarbons and semiconducting nanocarbons included in the dispersion liquid from the physical state or the chemical state.

A method for integrally forming a graphene film (GF) of a high specific surface area (SSA) by ultrafast ultraviolet (UV) laser processing, includes: selecting a carbon precursor material, where the carbon precursor material is one selected from the group consisting of a biomass/hydrogel composite and a heavy hydrocarbon compound; adding an activator solution to an inside of the carbon precursor material to obtain a composite with an activator uniformly loaded, and spreading the composite on a flexible substrate to form a carbon precursor material layer; heating and drying the carbon precursor material layer; in-situ processing with an ultrafast UV laser to obtain an activated GF of a high SSA; and cleaning and drying the activated GF. With the method of the present disclosure, a microporous activated GF of a high SSA can be directly processed in-situ on a flexible substrate.

A method for integrally forming a graphene film (GF) of a high specific surface area (SSA) by ultrafast ultraviolet (UV) laser processing, includes: selecting a carbon precursor material, where the carbon precursor material is one selected from the group consisting of a biomass/hydrogel composite and a heavy hydrocarbon compound; adding an activator solution to an inside of the carbon precursor material to obtain a composite with an activator uniformly loaded, and spreading the composite on a flexible substrate to form a carbon precursor material layer; heating and drying the carbon precursor material layer; in-situ processing with an ultrafast UV laser to obtain an activated GF of a high SSA; and cleaning and drying the activated GF. With the method of the present disclosure, a microporous activated GF of a high SSA can be directly processed in-situ on a flexible substrate.