A method of producing a graphene suspension, comprising: (a) mixing multiple particles of a graphitic material and multiple particles of a solid carrier material to form a mixture in an impacting chamber of an energy impacting apparatus; (b) operating the energy impacting apparatus with a frequency and an intensity for a length of time sufficient for peeling off graphene sheets from the graphitic material and transferring the graphene sheets to surfaces of the carrier material particles to produce graphene-coated carrier particles inside the impacting chamber; and (c) dispersing the graphene-coated carrier particles in a liquid medium and separating the graphene sheets from the carrier material particles using ultrasonication or mechanical shearing means and removing the carrier material from the liquid medium to produce the graphene suspension. The process is fast (1-4 hours as opposed to 5-120 hours of conventional processes), environmentally benign, cost effective, and highly scalable.

Described embodiments include a graphene membrane film for solvent purification and related method, and a solvent purification system using same. The graphene membrane film for solvent purification is formed having a plurality of stacked graphene plate-shaped flakes, and at least one pair of the plurality of stacked graphene plate-shaped flakes comprises a physical bond or a chemical bond connecting layers. The graphene membrane film for solvent purification is produced by preparing a graphene oxide dispersion liquid by dispersing graphene oxide in distilled water; confining the graphene oxide dispersion liquid between a pair of substrates; and applying heat and pressure to the graphene oxide dispersion liquid between the substrates to perform a hydrothermal reaction to concurrently thermally reduce the graphene oxide and bind graphenes. Due to lipophilic surface property and fine pores, size exclusion separation and hydrophilic-lipophilic component separation through polarity may be realized, and thus is usable in fine chemistry fields.

Described embodiments include a graphene membrane film for solvent purification and related method, and a solvent purification system using same. The graphene membrane film for solvent purification is formed having a plurality of stacked graphene plate-shaped flakes, and at least one pair of the plurality of stacked graphene plate-shaped flakes comprises a physical bond or a chemical bond connecting layers. The graphene membrane film for solvent purification is produced by preparing a graphene oxide dispersion liquid by dispersing graphene oxide in distilled water; confining the graphene oxide dispersion liquid between a pair of substrates; and applying heat and pressure to the graphene oxide dispersion liquid between the substrates to perform a hydrothermal reaction to concurrently thermally reduce the graphene oxide and bind graphenes. Due to lipophilic surface property and fine pores, size exclusion separation and hydrophilic-lipophilic component separation through polarity may be realized, and thus is usable in fine chemistry fields.

An electrode material of a supercapacitor includes a negative material prepared by the following steps: first dispersing graphite oxide in deionized water; after stirring and ultrasonic treatment, reducing the graphite oxide into reduced graphene oxide by using a hydrazine hydrate, and vacuum drying at 40-80° C.; dispersing the reduced graphene oxide in a DMF solution with 2,6-diaminoanthraquinone, and stirring and performing the ultrasonic treatment again; at 60-90° C., adding isoamyl nitrite, and reacting for 18-24 h; and washing reaction products with ethanol and deionized water for multiple times, and finally freeze drying to obtain a product.

An electrode material of a supercapacitor includes a negative material prepared by the following steps: first dispersing graphite oxide in deionized water; after stirring and ultrasonic treatment, reducing the graphite oxide into reduced graphene oxide by using a hydrazine hydrate, and vacuum drying at 40-80° C.; dispersing the reduced graphene oxide in a DMF solution with 2,6-diaminoanthraquinone, and stirring and performing the ultrasonic treatment again; at 60-90° C., adding isoamyl nitrite, and reacting for 18-24 h; and washing reaction products with ethanol and deionized water for multiple times, and finally freeze drying to obtain a product.

The present disclosure features a Janus composite having a hydrophobic nanoparticulate component and a 2- or 3-dimensional hydrophilic framework, and materials, systems, methods of making the Janus composite and methods of using the Janus composite for separating oil from an oil-in-water emulsion. For example, Janus composites with MoS2 nanospheres on/in a hydrophilic reduced graphene oxide (rGO) or cellulose acetate framework are provided.

The present invention relates in part to a method of fabricating graphene structures from graphene oxide by reducing the graphene oxide on a patterned substrate. The invention also relates in part to graphene structures produced using said method and electrodes and capacitors comprising said graphene structures.

The present invention relates in part to a method of fabricating graphene structures from graphene oxide by reducing the graphene oxide on a patterned substrate. The invention also relates in part to graphene structures produced using said method and electrodes and capacitors comprising said graphene structures.

A graphene foam-protected selenium cathode layer for an alkali metal-selenium cell, comprising: (a) a sheet or a roll of solid graphene foam composed of multiple pores and pore walls containing graphene sheets, wherein the graphene sheets contain a pristine graphene material having less than 0.01% by weight of non-carbon elements or a non-pristine graphene material having 0.01% to 20% by weight of non-carbon elements, wherein said non-pristine graphene is selected from graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydrogenated graphene, nitrogenated graphene, boron-doped graphene, nitrogen-doped graphene, chemically functionalized graphene, or a combination thereof, wherein the graphene sheets are interconnected or chemically merged together without an adhesive resin; and (b) selenium coating or particles residing in the pores or bonded to the pore walls of the solid graphene foam.

A graphene foam-protected selenium cathode layer for an alkali metal-selenium cell, comprising: (a) a sheet or a roll of solid graphene foam composed of multiple pores and pore walls containing graphene sheets, wherein the graphene sheets contain a pristine graphene material having less than 0.01% by weight of non-carbon elements or a non-pristine graphene material having 0.01% to 20% by weight of non-carbon elements, wherein said non-pristine graphene is selected from graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydrogenated graphene, nitrogenated graphene, boron-doped graphene, nitrogen-doped graphene, chemically functionalized graphene, or a combination thereof, wherein the graphene sheets are interconnected or chemically merged together without an adhesive resin; and (b) selenium coating or particles residing in the pores or bonded to the pore walls of the solid graphene foam.