Compositions comprising hydrogenated and dehydrogenated graphite comprising a plurality of flakes. At least one flake in ten has a size in excess of ten square micrometers. For example, the flakes can have an average thickness of 10 atomic layers or less.

Compositions comprising hydrogenated and dehydrogenated graphite comprising a plurality of flakes. At least one flake in ten has a size in excess of ten square micrometers. For example, the flakes can have an average thickness of 10 atomic layers or less.

A method of producing graphene sheets from coke or coal powder, comprising: (a) forming an intercalated coke or coal compound by electrochemical intercalation conducted in an intercalation reactor, which contains (i) a liquid solution electrolyte comprising an intercalating agent; (ii) a working electrode that contains the powder in ionic contact with the liquid electrolyte, wherein the coke or coal powder is selected from petroleum coke, coal-derived coke, meso-phase coke, synthetic coke, leonardite, lignite coal, or natural coal mineral powder; and (iii) a counter electrode in ionic contact with the electrolyte, and wherein a current is imposed upon the working electrode and the counter electrode for effecting electrochemical intercalation of the intercalating agent into the powder; and (b) exfoliating and separating graphene planes from the intercalated coke or coal compound using an ultrasonication, thermal shock exposure, mechanical shearing treatment, or a combination thereof to produce isolated graphene sheets.

A method of producing graphene sheets from coke or coal powder, comprising: (a) forming an intercalated coke or coal compound by electrochemical intercalation conducted in an intercalation reactor, which contains (i) a liquid solution electrolyte comprising an intercalating agent; (ii) a working electrode that contains the powder in ionic contact with the liquid electrolyte, wherein the coke or coal powder is selected from petroleum coke, coal-derived coke, meso-phase coke, synthetic coke, leonardite, lignite coal, or natural coal mineral powder; and (iii) a counter electrode in ionic contact with the electrolyte, and wherein a current is imposed upon the working electrode and the counter electrode for effecting electrochemical intercalation of the intercalating agent into the powder; and (b) exfoliating and separating graphene planes from the intercalated coke or coal compound using an ultrasonication, thermal shock exposure, mechanical shearing treatment, or a combination thereof to produce isolated graphene sheets.

A device for performing electrolysis of water is disclosed. The device comprising: a semiconductor structure comprising a surface and an electron guiding layer below said surface, the electron guiding layer of the semiconductor structure being configured to guide electron movement in a plane parallel to the surface, the electron guiding layer of the semiconductor structure comprising an InGaN quantum well or a heterojunction, the heterojunction being a junction between AlN material and GaN material or between AlGaN material and GaN material; at least one metal cathode arranged on the surface of the semiconductor structure; and at least one photoanode arranged on the surface of the semiconductor structure, wherein the at least one photoanode comprises a plurality of quantum dots of In.sub.xGa.sub.(1−x)N material, wherein 0.4≤x≤1. A system comprising such device is also disclosed.

A method of producing an electrochemically derived graphene oxide and product produced therefrom. The method comprises locating graphite particles within an electrochemical cell having a working electrode, counter electrode, and an aqueous acid electrolyte, the working electrode being positioned within the electrolyte to contact at least a portion of the graphite particles; agitating the graphite particles within the electrolyte; and applying a potential difference between the working electrode and counter electrode, thereby resulting in electrochemical exfoliation and oxidation of the graphite particles to produce graphene oxide.

A method of producing an electrochemically derived graphene oxide and product produced therefrom. The method comprises locating graphite particles within an electrochemical cell having a working electrode, counter electrode, and an aqueous acid electrolyte, the working electrode being positioned within the electrolyte to contact at least a portion of the graphite particles; agitating the graphite particles within the electrolyte; and applying a potential difference between the working electrode and counter electrode, thereby resulting in electrochemical exfoliation and oxidation of the graphite particles to produce graphene oxide.

A composite for a porous transport layer may include a particulate substrate including at least one selected from a group consisting of an oxide of a first metal and a second metal, and nanoparticles of a third metal formed on a surface of the particulate substrate, a sintered body thereof, and a method for preparing the same.

A composite for a porous transport layer may include a particulate substrate including at least one selected from a group consisting of an oxide of a first metal and a second metal, and nanoparticles of a third metal formed on a surface of the particulate substrate, a sintered body thereof, and a method for preparing the same.

The present invention relates to an electrode assembly and an electrolyser using one or more of said assemblies, in particular the present invention provides an electrode assembly for the production of hydrogen comprising: i) an anode structure which comprises an anode located within an electrolysis compartment, ii) a cathode structure which comprises a cathode located within an electrolysis compartment containing a solution of an alkali metal hydroxide, characterised in that the cathode comprises: a) An electrically conductive metal substrate, and b) An electrocatalytic layer on the substrate and comprising a, at least one metal selected from platinum group metals, rhenium, nickel, cobalt and molybdenum and b. at least 50% by volume of an electrically conductive support material, wherein the electrically conductive support material is formed from particles having an average particle size of less than 5 microns (5 μm) and which are not metallic particles.